diff --git a/css/style.css b/css/style.css
index 9bda381..1879945 100644
--- a/css/style.css
+++ b/css/style.css
@@ -111,3 +111,15 @@ esp-web-install-button button, .install-btn {
 .customize p { margin: 8px 0 0; color: var(--dim); }
 .customize code { background: var(--bg-blue-tint); padding: 1px 5px; border-radius: 4px; }
 .error-box { border-left: 3px solid var(--border-error); background: var(--bg-error); border-radius: 0 8px 8px 0; padding: 12px 16px; }
+
+/* Firmware config view/download */
+.config { border-left: 3px solid var(--blue); background: var(--bg-blue-tint); border-radius: 0 8px 8px 0; padding: 12px 16px; margin-top: 14px; }
+.config > summary { cursor: pointer; font-weight: 700; }
+.config-hint { margin: 10px 0 8px; color: var(--dim); font-size: .85rem; }
+.config-hint code { background: var(--panel); border: 1px solid var(--line); padding: 1px 5px; border-radius: 4px; }
+.config-yaml { margin: 0; background: var(--panel); border: 1px solid var(--line); border-radius: 8px; padding: 12px 14px; overflow: auto; max-height: 340px; }
+.config-yaml code { font-family: ui-monospace, Consolas, monospace; font-size: .8rem; line-height: 1.5; white-space: pre; color: var(--ink); }
+.config-actions { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; margin-top: 12px; }
+.config-download { background: var(--blue); color: #fff; border: 0; border-radius: 8px; padding: 9px 18px; font-size: .9rem; font-weight: 700; cursor: pointer; }
+.config-download:disabled { opacity: .55; cursor: default; }
+.config-github { font-size: .86rem; font-weight: 600; }
diff --git a/devices.json b/devices.json
index 4c0883e..012c6a7 100644
--- a/devices.json
+++ b/devices.json
@@ -14,6 +14,11 @@
         "stable": {
           "Standard": "https://apolloautomation.github.io/MSR-1/firmware/manifest.json"
         }
+      },
+      "config": {
+        "stable": {
+          "Standard": "https://raw.githubusercontent.com/ApolloAutomation/MSR-1/main/Integrations/ESPHome/MSR-1_Factory.yaml"
+        }
       }
     },
     {
@@ -30,6 +35,11 @@
         "stable": {
           "Standard": "https://apolloautomation.github.io/MSR-2/firmware/manifest.json"
         }
+      },
+      "config": {
+        "stable": {
+          "Standard": "https://raw.githubusercontent.com/ApolloAutomation/MSR-2/main/Integrations/ESPHome/MSR-2_Factory.yaml"
+        }
       }
     },
     {
@@ -46,6 +56,11 @@
         "stable": {
           "Standard": "https://apolloautomation.github.io/MTR-1/firmware/manifest.json"
         }
+      },
+      "config": {
+        "stable": {
+          "Standard": "https://raw.githubusercontent.com/ApolloAutomation/MTR-1/main/Integrations/ESPHome/MTR-1_Factory.yaml"
+        }
       }
     },
     {
@@ -63,6 +78,12 @@
           "WiFi": "https://apolloautomation.github.io/R_PRO-1/firmware-w/manifest.json",
           "Ethernet": "https://apolloautomation.github.io/R_PRO-1/firmware-e/manifest.json"
         }
+      },
+      "config": {
+        "stable": {
+          "WiFi": "https://raw.githubusercontent.com/ApolloAutomation/R_PRO-1/main/Integrations/ESPHome/R_PRO-1_W.yaml",
+          "Ethernet": "https://raw.githubusercontent.com/ApolloAutomation/R_PRO-1/main/Integrations/ESPHome/R_PRO-1_ETH.yaml"
+        }
       }
     },
     {
@@ -79,6 +100,11 @@
         "stable": {
           "Standard": "https://apolloautomation.github.io/AIR-1/firmware/manifest.json"
         }
+      },
+      "config": {
+        "stable": {
+          "Standard": "https://raw.githubusercontent.com/ApolloAutomation/AIR-1/main/Integrations/ESPHome/AIR-1_Factory.yaml"
+        }
       }
     },
     {
@@ -95,6 +121,11 @@
         "stable": {
           "Standard": "https://apolloautomation.github.io/TEMP-1/firmware/manifest.json"
         }
+      },
+      "config": {
+        "stable": {
+          "Standard": "https://raw.githubusercontent.com/ApolloAutomation/TEMP-1/main/Integrations/ESPHome/TEMP-1_R2.yaml"
+        }
       }
     },
     {
@@ -111,6 +142,11 @@
         "stable": {
           "Standard": "https://apolloautomation.github.io/PLT-1/firmware/manifest.json"
         }
+      },
+      "config": {
+        "stable": {
+          "Standard": "https://raw.githubusercontent.com/ApolloAutomation/PLT-1/main/Integrations/ESPHome/PLT-1.yaml"
+        }
       }
     },
     {
@@ -128,6 +164,12 @@
           "WiFi": "https://apolloautomation.github.io/CAST-1/firmware-w/manifest.json",
           "Ethernet": "https://apolloautomation.github.io/CAST-1/firmware-e/manifest.json"
         }
+      },
+      "config": {
+        "stable": {
+          "WiFi": "https://raw.githubusercontent.com/ApolloAutomation/CAST-1/main/Integrations/ESPHome/CAST-1_W.yaml",
+          "Ethernet": "https://raw.githubusercontent.com/ApolloAutomation/CAST-1/main/Integrations/ESPHome/CAST-1_ETH.yaml"
+        }
       }
     },
     {
@@ -144,6 +186,11 @@
         "stable": {
           "Standard": "https://apolloautomation.github.io/PUMP-1/firmware/manifest.json"
         }
+      },
+      "config": {
+        "stable": {
+          "Standard": "https://raw.githubusercontent.com/ApolloAutomation/PUMP-1/main/Integrations/ESPHome/PUMP-1.yaml"
+        }
       }
     },
     {
@@ -160,6 +207,11 @@
         "stable": {
           "Standard": "https://apolloautomation.github.io/BTN-1/firmware/manifest.json"
         }
+      },
+      "config": {
+        "stable": {
+          "Standard": "https://raw.githubusercontent.com/ApolloAutomation/BTN-1/main/Integrations/ESPHome/BTN-1.yaml"
+        }
       }
     }
   ]
diff --git a/docs/superpowers/plans/2026-07-09-yaml-view-download.md b/docs/superpowers/plans/2026-07-09-yaml-view-download.md
new file mode 100644
index 0000000..6cd22ad
--- /dev/null
+++ b/docs/superpowers/plans/2026-07-09-yaml-view-download.md
@@ -0,0 +1,507 @@
+# YAML View / Download — Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** On each device page, view and download the ESPHome config (YAML) for the selected firmware variant, so a user can rebuild/reflash and have the device onboard like a factory unit.
+
+**Architecture:** A `config` map in `devices.json` mirrors `firmware` (channel → variant → raw YAML URL). `js/views/device.js` gains a collapsible block in step 1 that follows the variant selection: it fetches the raw YAML live from `raw.githubusercontent.com`, shows it (via `textContent`, which escapes), offers a Blob download with the real filename, and links to the derived GitHub blob URL. The three ad-hoc async staleness guards are unified into one render-epoch counter. The validator gains a reachability + shape check for config URLs.
+
+**Tech Stack:** Vanilla ES modules (no build), Python stdlib validator, Playwright, GitHub raw hosting.
+
+## Global Constraints
+
+- No build step, no framework, no dependency outside `tests/`. (AGENTS.md)
+- `devices.json` is the single source of truth; views, scripts, and tests all read it.
+- Runtime-fetched content (the YAML) must be escaped before display. Here we set it via
+  `element.textContent`, which is inherently safe; registry-derived values (variant key,
+  filename, `device.wiki`, `device.name`) are trusted repo content and interpolated as-is,
+  matching existing code.
+- Live fetch only — **no cache directory**, so `.github/workflows/pages.yml` cp-list is
+  **unchanged**. Do not add a new top-level runtime file/dir.
+- A wrong-config link is a firmware-safety failure mode: async config renders must guard
+  against a selection change mid-fetch (the render-epoch mechanism).
+- Commits: author `8107750+bharvey88@users.noreply.github.com`; end messages with
+  `🤖 Generated with [Claude Code](https://claude.com/claude-code)`; NEVER `Co-Authored-By: Claude`.
+  Use `git commit -F <ascii temp file>` (Windows PowerShell), never `-m` multiline.
+- Branch: `feat/3-yaml-view-download` (already created off `main`). PR targets `main`.
+- Tests keyed off `devices.json` (data-driven), never hardcoded device ids.
+
+**Config URL map to add (Task 2), all `https://raw.githubusercontent.com/ApolloAutomation/<REPO>/main/Integrations/ESPHome/<FILE>`:**
+
+| device | channel/variant | file |
+|--------|-----------------|------|
+| msr-1 | stable/Standard | MSR-1_Factory.yaml |
+| msr-2 | stable/Standard | MSR-2_Factory.yaml |
+| mtr-1 | stable/Standard | MTR-1_Factory.yaml |
+| air-1 | stable/Standard | AIR-1_Factory.yaml |
+| r-pro-1 | stable/WiFi | R_PRO-1_W.yaml |
+| r-pro-1 | stable/Ethernet | R_PRO-1_ETH.yaml |
+| cast-1 | stable/WiFi | CAST-1_W.yaml |
+| cast-1 | stable/Ethernet | CAST-1_ETH.yaml |
+| pump-1 | stable/Standard | PUMP-1.yaml |
+| btn-1 | stable/Standard | BTN-1.yaml |
+| temp-1 | stable/Standard | TEMP-1_R2.yaml |
+| plt-1 | stable/Standard | PLT-1.yaml |
+
+`temp-1`/`plt-1` map to the non-battery configs (confirmed by Brandon: the battery TEMP-1B/PLT-1B
+are separate products not in `devices.json`). All 10 devices get a `config`.
+
+---
+
+## Task 1: Validator — config shape + reachability
+
+**Files:**
+- Modify: `scripts/validate_registry.py`
+- Test: `scripts/test_validate_registry.py`
+
+**Interfaces:**
+- Produces: `check_config_shape(config, dev_id) -> list[str]` (pure). `main()` also HEAD-checks
+  every `config` URL via the existing `head_ok`.
+
+- [ ] **Step 1: Write failing unit tests**
+
+Add to `scripts/test_validate_registry.py` (new class):
+
+```python
+class ConfigShape(unittest.TestCase):
+    def test_good_config_has_no_errors(self):
+        cfg = {"stable": {"WiFi": "https://raw.githubusercontent.com/o/r/main/a.yaml"}}
+        self.assertEqual(vr.check_config_shape(cfg, "r-pro-1"), [])
+
+    def test_non_string_url_errors(self):
+        cfg = {"stable": {"WiFi": 123}}
+        errs = vr.check_config_shape(cfg, "r-pro-1")
+        self.assertTrue(any("WiFi" in e for e in errs), errs)
+
+    def test_non_https_url_errors(self):
+        cfg = {"stable": {"Standard": "http://insecure/a.yaml"}}
+        errs = vr.check_config_shape(cfg, "x")
+        self.assertTrue(any("https" in e for e in errs), errs)
+
+    def test_channel_not_object_errors(self):
+        cfg = {"stable": "oops"}
+        errs = vr.check_config_shape(cfg, "x")
+        self.assertTrue(any("stable" in e for e in errs), errs)
+```
+
+- [ ] **Step 2: Run tests, verify they fail**
+
+Run: `python scripts/test_validate_registry.py`
+Expected: FAIL — `module 'validate_registry' has no attribute 'check_config_shape'`.
+
+- [ ] **Step 3: Implement `check_config_shape` and wire reachability into `main`**
+
+In `scripts/validate_registry.py`, add after `check_manifest_shape`:
+
+```python
+def check_config_shape(config, dev_id):
+    """Validate the optional `config` map (channel -> variant -> https URL).
+
+    Returns a list of error strings (empty when sound). Network-free.
+    """
+    errs = []
+    for channel, variants in config.items():
+        if not isinstance(variants, dict):
+            errs.append(f"{dev_id} config {channel}: not an object")
+            continue
+        for variant, url in variants.items():
+            if not isinstance(url, str) or not url.startswith("https://"):
+                errs.append(f"{dev_id} config {channel}/{variant}: not an https URL")
+    return errs
+```
+
+In `main()`, inside the `for dev in reg["devices"]:` loop, after the firmware loop, add:
+
+```python
+        config = dev.get("config", {})
+        errors.extend(check_config_shape(config, dev["id"]))
+        for channel, variants in config.items():
+            if not isinstance(variants, dict):
+                continue
+            for variant, curl in variants.items():
+                if isinstance(curl, str) and not head_ok(curl):
+                    errors.append(f"{dev['id']} config {channel}/{variant}: unreachable: {curl}")
+```
+
+- [ ] **Step 4: Run unit tests, verify they pass**
+
+Run: `python scripts/test_validate_registry.py`
+Expected: PASS (all classes).
+
+- [ ] **Step 5: Commit**
+
+Write message to an ASCII temp file and commit:
+
+```bash
+git add scripts/validate_registry.py scripts/test_validate_registry.py
+git commit -F <ascii-msg-file>   # subject: "Validate config URLs in the registry"
+```
+
+---
+
+## Task 2: Populate `config` in devices.json
+
+**Files:**
+- Modify: `devices.json`
+
+**Interfaces:**
+- Produces: a `config` object on 8 devices, mirroring their `firmware` channel/variant keys.
+
+- [ ] **Step 1: Add the `config` map to each of the 8 devices**
+
+For each device below, add a sibling `config` key next to `firmware`. Exact values (branch `main`,
+path `Integrations/ESPHome/`). Example for `r-pro-1`:
+
+```json
+      "firmware": {
+        "stable": {
+          "WiFi": "https://apolloautomation.github.io/R_PRO-1/firmware-w/manifest.json",
+          "Ethernet": "https://apolloautomation.github.io/R_PRO-1/firmware-e/manifest.json"
+        }
+      },
+      "config": {
+        "stable": {
+          "WiFi": "https://raw.githubusercontent.com/ApolloAutomation/R_PRO-1/main/Integrations/ESPHome/R_PRO-1_W.yaml",
+          "Ethernet": "https://raw.githubusercontent.com/ApolloAutomation/R_PRO-1/main/Integrations/ESPHome/R_PRO-1_ETH.yaml"
+        }
+      },
+```
+
+Full list of `config` values (variant key must exactly match the device's `firmware` variant key):
+- `msr-1` stable/Standard → `…/ApolloAutomation/MSR-1/main/Integrations/ESPHome/MSR-1_Factory.yaml`
+- `msr-2` stable/Standard → `…/MSR-2/main/Integrations/ESPHome/MSR-2_Factory.yaml`
+- `mtr-1` stable/Standard → `…/MTR-1/main/Integrations/ESPHome/MTR-1_Factory.yaml`
+- `air-1` stable/Standard → `…/AIR-1/main/Integrations/ESPHome/AIR-1_Factory.yaml`
+- `r-pro-1` stable/WiFi → `…/R_PRO-1/main/Integrations/ESPHome/R_PRO-1_W.yaml`; Ethernet → `R_PRO-1_ETH.yaml`
+- `cast-1` stable/WiFi → `…/CAST-1/main/Integrations/ESPHome/CAST-1_W.yaml`; Ethernet → `CAST-1_ETH.yaml`
+- `pump-1` stable/Standard → `…/PUMP-1/main/Integrations/ESPHome/PUMP-1.yaml`
+- `btn-1` stable/Standard → `…/BTN-1/main/Integrations/ESPHome/BTN-1.yaml`
+- `temp-1` stable/Standard → `…/TEMP-1/main/Integrations/ESPHome/TEMP-1_R2.yaml`
+- `plt-1` stable/Standard → `…/PLT-1/main/Integrations/ESPHome/PLT-1.yaml`
+
+- [ ] **Step 2: Validate (shape + reachability + manifests)**
+
+Run: `python scripts/validate_registry.py`
+Expected: `Registry OK: all manifests live and complete.` (also confirms every `config` URL is HTTP 200).
+If any config URL 404s, fix the filename/branch for that device and re-run.
+
+- [ ] **Step 3: Commit**
+
+```bash
+git add devices.json
+git commit -F <ascii-msg-file>   # subject: "Add per-variant config URLs to the registry"
+```
+
+---
+
+## Task 3: Render-epoch refactor in device.js
+
+The existing late-manifest Playwright tests are the safety net for this behavior-preserving
+refactor: they must stay green after the three ad-hoc guards become one epoch counter.
+
+**Files:**
+- Modify: `js/views/device.js`
+- Test (existing, must stay green): `tests/installer.spec.js` (the two "late manifest fetch" tests)
+
+**Interfaces:**
+- Produces: a `renderDevice`-scoped `let epoch = 0;` incremented on every channel/variant change;
+  `renderInstall`/`renderReleaseNotes` capture `const myEpoch = epoch;` and bail on `epoch !== myEpoch`.
+
+- [ ] **Step 1: Add the epoch counter**
+
+In `renderDevice`, next to the `let channel`/`let variant` declarations, add:
+
+```js
+  let epoch = 0; // bumps on every channel/variant change; async renders bail if it moved
+```
+
+- [ ] **Step 2: Convert `renderInstall`'s guards to epoch**
+
+At the top of `renderInstall`, add `const myEpoch = epoch;` as the first line. Remove the
+`const want = manifest;` line. Replace both `if (selectedManifest(device, channel, variant) !== want) return;`
+lines with:
+
+```js
+        if (epoch !== myEpoch) return; // selection changed mid-fetch
+```
+
+- [ ] **Step 3: Convert `renderReleaseNotes`'s guards to epoch**
+
+In `renderReleaseNotes`, replace `const want = channel;` with `const myEpoch = epoch;`, and replace
+both `if (channel !== want) return;` lines with:
+
+```js
+      if (epoch !== myEpoch) return; // selection changed mid-fetch
+```
+
+- [ ] **Step 4: Bump epoch in the two seg click handlers**
+
+In the variant seg handler (inside `renderVariantSeg`), right after `variant = b.dataset.variant;` add `epoch++;`.
+In the channel seg handler, right after `variant = Object.keys(device.firmware[channel])[0];` add `epoch++;`.
+
+- [ ] **Step 5: Run the suite, verify still green**
+
+Run: `cd tests && npx playwright test`
+Expected: all existing tests PASS (especially the two "late manifest fetch …" tests).
+
+- [ ] **Step 6: Commit**
+
+```bash
+git add js/views/device.js
+git commit -F <ascii-msg-file>   # subject: "Unify device.js async staleness guards into one render epoch"
+```
+
+---
+
+## Task 4: Config block — view, download, GitHub link
+
+**Files:**
+- Modify: `js/views/device.js`, `css/style.css`
+- Test: `tests/installer.spec.js`
+
+**Interfaces:**
+- Consumes: `epoch`, `channel`, `variant`, `device`, `el` (from `renderDevice`); `device.config`.
+- Produces: module helpers `rawToBlob(raw)`, `configBasename(url)`, `downloadText(text, filename)`;
+  a `renderDevice`-scoped `renderConfig()`; a `#config-slot` in step 1; `.config*` CSS.
+
+- [ ] **Step 1: Write the failing "renders + links" test**
+
+Add to `tests/installer.spec.js`:
+
+```js
+function blobFromRaw(raw) {
+  const m = raw.match(/^https:\/\/raw\.githubusercontent\.com\/([^/]+)\/([^/]+)\/([^/]+)\/(.+)$/);
+  return `https://github.com/${m[1]}/${m[2]}/blob/${m[3]}/${m[4]}`;
+}
+function defaultSel(d) {
+  const channels = Object.keys(d.firmware);
+  const channel = channels.includes('stable') ? 'stable' : channels[0];
+  const variant = Object.keys(d.firmware[channel])[0];
+  return { channel, variant, url: d.config && d.config[channel] && d.config[channel][variant] };
+}
+
+test('device config: reflash section renders the fetched YAML and derived GitHub link', async ({ page }) => {
+  const d = registry.devices.find((x) => x.config && defaultSel(x).url);
+  test.skip(!d, 'no device has a config for its default selection');
+  const { url } = defaultSel(d);
+  await page.route(url, (route) => route.fulfill({ contentType: 'text/plain', body: 'esphome:\n  name: mock-cfg\n' }));
+  await page.goto(`/#/${d.id}`);
+  await expect(page.locator('.config')).toBeVisible();
+  await expect(page.locator('.config-yaml code')).toContainText('mock-cfg');
+  await expect(page.locator('.config-github')).toHaveAttribute('href', blobFromRaw(url));
+});
+```
+
+- [ ] **Step 2: Run it, verify it fails**
+
+Run: `cd tests && npx playwright test -g "reflash section renders"`
+Expected: FAIL — `.config` not found.
+
+- [ ] **Step 3: Add module helpers to device.js**
+
+At module scope in `js/views/device.js` (after `esc`), add:
+
+```js
+function rawToBlob(raw) {
+  const m = raw.match(/^https:\/\/raw\.githubusercontent\.com\/([^/]+)\/([^/]+)\/([^/]+)\/(.+)$/);
+  return m ? `https://github.com/${m[1]}/${m[2]}/blob/${m[3]}/${m[4]}` : raw;
+}
+function configBasename(url) {
+  return (url.split('/').pop() || 'config.yaml').replace(/[^\w.\-]/g, '_');
+}
+function downloadText(text, filename) {
+  const blob = new Blob([text], { type: 'text/yaml' });
+  const url = URL.createObjectURL(blob);
+  const a = document.createElement('a');
+  a.href = url; a.download = filename;
+  document.body.appendChild(a); a.click(); a.remove();
+  setTimeout(() => URL.revokeObjectURL(url), 1000);
+}
+```
+
+- [ ] **Step 4: Add the `#config-slot` to step 1**
+
+In the `el.innerHTML` template, immediately after `<div id="release-slot"></div>`, add:
+
+```js
+        <div id="config-slot"></div>
+```
+
+- [ ] **Step 5: Add `renderConfig()` and call it**
+
+Inside `renderDevice` (near `renderReleaseNotes`), add:
+
+```js
+  async function renderConfig() {
+    const slot = el.querySelector('#config-slot');
+    const url = device.config && device.config[channel] && device.config[channel][variant];
+    if (!url) { slot.innerHTML = ''; return; }
+    const filename = configBasename(url);
+    slot.innerHTML = `
+      <details class="config">
+        <summary>Build or reflash this firmware yourself</summary>
+        <p class="config-hint">The ESPHome config for the <strong>${variant}</strong> variant
+          (<code>${filename}</code>). Rebuilding from this keeps the device's onboarding, so the
+          <a href="${device.wiki}">${device.name} wiki</a> setup steps still apply.</p>
+        <pre class="config-yaml"><code>Loading config…</code></pre>
+        <div class="config-actions">
+          <button class="config-download" disabled>Download .yaml</button>
+          <a class="config-github" href="${rawToBlob(url)}" target="_blank" rel="noopener">View on GitHub →</a>
+        </div>
+      </details>`;
+    const codeEl = slot.querySelector('.config-yaml code');
+    const dlBtn = slot.querySelector('.config-download');
+    const myEpoch = epoch;
+    try {
+      const res = await fetch(url);
+      if (!res.ok) throw new Error('HTTP ' + res.status);
+      const text = await res.text();
+      if (epoch !== myEpoch) return; // selection changed mid-fetch
+      codeEl.textContent = text; // textContent escapes the runtime-fetched YAML
+      dlBtn.disabled = false;
+      dlBtn.addEventListener('click', () => downloadText(text, filename));
+    } catch {
+      if (epoch !== myEpoch) return;
+      codeEl.textContent = 'Could not load the config here — use “View on GitHub”.';
+    }
+  }
+```
+
+Call it in three places: (a) in the initial render block at the bottom, add `renderConfig();` after
+`renderReleaseNotes();`; (b) in the variant seg handler, after `renderInstall();` add `renderConfig();`;
+(c) in the channel seg handler, after `renderReleaseNotes();` add `renderConfig();`.
+
+- [ ] **Step 6: Add CSS**
+
+Append to `css/style.css`:
+
+```css
+/* Firmware config view/download */
+.config { border-left: 3px solid var(--blue); background: var(--bg-blue-tint); border-radius: 0 8px 8px 0; padding: 12px 16px; margin-top: 14px; }
+.config > summary { cursor: pointer; font-weight: 700; }
+.config-hint { margin: 10px 0 8px; color: var(--dim); font-size: .85rem; }
+.config-hint code { background: var(--panel); border: 1px solid var(--line); padding: 1px 5px; border-radius: 4px; }
+.config-yaml { margin: 0; background: var(--panel); border: 1px solid var(--line); border-radius: 8px; padding: 12px 14px; overflow: auto; max-height: 340px; }
+.config-yaml code { font-family: ui-monospace, Consolas, monospace; font-size: .8rem; line-height: 1.5; white-space: pre; color: var(--ink); }
+.config-actions { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; margin-top: 12px; }
+.config-download { background: var(--blue); color: #fff; border: 0; border-radius: 8px; padding: 9px 18px; font-size: .9rem; font-weight: 700; cursor: pointer; }
+.config-download:disabled { opacity: .55; cursor: default; }
+.config-github { font-size: .86rem; font-weight: 600; }
+```
+
+- [ ] **Step 7: Run the test, verify it passes**
+
+Run: `cd tests && npx playwright test -g "reflash section renders"`
+Expected: PASS.
+
+- [ ] **Step 8: Commit**
+
+```bash
+git add js/views/device.js css/style.css tests/installer.spec.js
+git commit -F <ascii-msg-file>   # subject: "Add firmware config view/download to device pages"
+```
+
+---
+
+## Task 5: Config tests — variant switch, stale guard, download, no-config
+
+**Files:**
+- Test: `tests/installer.spec.js`
+
+- [ ] **Step 1: Add the four tests**
+
+```js
+test('device config: switching variant swaps the config', async ({ page }) => {
+  const d = registry.devices.find((x) => x.config && x.config.stable && Object.keys(x.config.stable).length > 1);
+  test.skip(!d, 'no multi-variant config device');
+  const variants = Object.keys(d.config.stable);
+  for (const v of variants) {
+    await page.route(d.config.stable[v], (route) =>
+      route.fulfill({ contentType: 'text/plain', body: `esphome:\n  name: cfg-${v}\n` }));
+  }
+  await page.goto(`/#/${d.id}`);
+  await expect(page.locator('.config-yaml code')).toContainText(`cfg-${variants[0]}`);
+  await page.locator(`#variant-seg button[data-variant="${variants[1]}"]`).click();
+  await expect(page.locator('.config-yaml code')).toContainText(`cfg-${variants[1]}`);
+});
+
+test('device config: a slow fetch for a deselected variant does not overwrite', async ({ page }) => {
+  const d = registry.devices.find((x) => x.config && x.config.stable && Object.keys(x.config.stable).length > 1);
+  test.skip(!d, 'no multi-variant config device');
+  const variants = Object.keys(d.config.stable);
+  await page.route(d.config.stable[variants[0]], async (route) => {
+    await new Promise((r) => setTimeout(r, 1500));
+    await route.fulfill({ contentType: 'text/plain', body: 'esphome:\n  name: cfg-slow-0\n' });
+  });
+  await page.route(d.config.stable[variants[1]], (route) =>
+    route.fulfill({ contentType: 'text/plain', body: 'esphome:\n  name: cfg-fast-1\n' }));
+  await page.goto(`/#/${d.id}`);
+  await page.locator(`#variant-seg button[data-variant="${variants[1]}"]`).click();
+  await page.waitForTimeout(2500);
+  await expect(page.locator('.config-yaml code')).toContainText('cfg-fast-1');
+  await expect(page.locator('.config-yaml code')).not.toContainText('cfg-slow-0');
+});
+
+test('device config: download uses the real filename', async ({ page }) => {
+  const d = registry.devices.find((x) => x.config && defaultSel(x).url);
+  test.skip(!d, 'no device has a config for its default selection');
+  const { url } = defaultSel(d);
+  await page.route(url, (route) => route.fulfill({ contentType: 'text/plain', body: 'esphome:\n' }));
+  await page.goto(`/#/${d.id}`);
+  await page.locator('.config summary').click(); // expand so the button is visible
+  const [download] = await Promise.all([
+    page.waitForEvent('download'),
+    page.locator('.config-download').click(),
+  ]);
+  expect(download.suggestedFilename()).toBe(url.split('/').pop());
+});
+
+test('device config: no section when the device has no config', async ({ page }) => {
+  const d = registry.devices.find((x) => !x.config);
+  test.skip(!d, 'every device has a config');
+  await page.goto(`/#/${d.id}`);
+  await expect(page.locator('.config')).toHaveCount(0);
+});
+```
+
+- [ ] **Step 2: Run the full suite, verify all pass**
+
+Run: `cd tests && npx playwright test`
+Expected: all PASS. The multi-variant tests exercise r-pro-1/cast-1. The "no section" test is
+data-driven and self-skips now that all 10 devices have a config — it's kept as a guard for any
+future config-less device (the `if (!url)` path).
+
+- [ ] **Step 3: Commit**
+
+```bash
+git add tests/installer.spec.js
+git commit -F <ascii-msg-file>   # subject: "Cover config view/download variant, stale, download, and empty cases"
+```
+
+---
+
+## Task 6: Full verification + PR
+
+- [ ] **Step 1: Run everything green**
+
+```bash
+python scripts/test_validate_registry.py            # offline unit tests
+python scripts/validate_registry.py                 # live: manifests + config URLs reachable
+cd tests && npx playwright test                     # full UI suite
+```
+Expected: all pass.
+
+- [ ] **Step 2: Independent review** — dispatch a code-review subagent over `git diff main` (focus:
+  epoch refactor correctness, config fetch escaping, download filename safety, deploy/no-cp-list,
+  data-driven tests). Address findings.
+
+- [ ] **Step 3: Push + open PR** targeting `main`, body per template, after showing Brandon the PR body.
+  Closes #3.
+
+## Self-review notes
+
+- Spec coverage: schema (T2), which-file rule (T2 map, all 10 devices mapped), UI view/download/GitHub
+  (T4), follows-variant (T4 handlers + T5), epoch refactor (T3), deploy/no-cp-list (constraints), validator
+  (T1), data-driven tests (T4/T5). Covered.
+- Follow-up (out of #3 scope): the battery products TEMP-1B / PLT-1B are not in `devices.json` as
+  installable devices — a separate registry-completeness item.
diff --git a/docs/superpowers/specs/2026-07-09-yaml-view-download-design.md b/docs/superpowers/specs/2026-07-09-yaml-view-download-design.md
new file mode 100644
index 0000000..25df585
--- /dev/null
+++ b/docs/superpowers/specs/2026-07-09-yaml-view-download-design.md
@@ -0,0 +1,155 @@
+# YAML View / Download on Device Pages — Design
+
+Date: 2026-07-09
+Status: Approved by Brandon (2026-07-09)
+Issue: #3
+
+## What we're building
+
+On each device page, a way to **view and download the ESPHome config (YAML)** for the
+selected firmware variant, so a user can rebuild or reflash the device from source and
+have it onboard exactly like a factory unit (following the wiki setup steps).
+
+This is the *reflash / rebuild* path, distinct from the *adopt-and-customize* path that
+#4 added to step 3 (ESPHome Dashboard "Take control", which uses `dashboard_import`).
+
+## Goals
+
+- Surface the config that reproduces a **properly-onboarding** device (improv-ble present),
+  so a reflash matches the wiki.
+- Follow the existing variant selection: on R_PRO-1 the WiFi and Ethernet configs are
+  different files, and switching the variant switches the config.
+- Adding a config is a **data change** (a URL in `devices.json`), not a code change.
+- No new deploy surface, no new dependency, no CDN hotlinking of firmware.
+
+## Non-goals
+
+- No local caching of YAML in the repo (no `yaml/` dir). We fetch live from GitHub raw,
+  so the config is always current and there is no `pages.yml` cp-list change.
+- Not the customize path — that is #4 (dashboard adoption). This section is framed as
+  "build/reflash from source", pointing at the wiki.
+- No YAML parsing, linting, or editing in the browser. View + download only.
+
+## Which config each variant points at
+
+The config that includes improv-ble (so a reflash onboards like new):
+
+- **`_Factory.yaml` when the repo has one** — older / smaller-flash devices that split the
+  improv-ble build out (e.g. `Integrations/ESPHome/MSR-2_Factory.yaml`).
+- **the main per-variant `<NAME>.yaml` otherwise** — newer devices that keep improv-ble
+  baked in permanently (e.g. R_PRO-1 has only `R_PRO-1_W.yaml` / `R_PRO-1_ETH.yaml`).
+
+The correct file per variant is determined by probing each repo during registry population.
+A device or variant with no mapped config simply shows no section (graceful).
+
+## Registry schema
+
+Add a `config` map that **mirrors `firmware`** (channel -> variant -> raw YAML URL). This is
+additive: `firmware` values stay plain manifest-URL strings, so existing firmware handling
+and tests are untouched.
+
+```json
+{
+  "id": "r-pro-1",
+  "repo": "ApolloAutomation/R_PRO-1",
+  "firmware": {
+    "stable": {
+      "WiFi": "https://apolloautomation.github.io/R_PRO-1/firmware-w/manifest.json",
+      "Ethernet": "https://apolloautomation.github.io/R_PRO-1/firmware-e/manifest.json"
+    }
+  },
+  "config": {
+    "stable": {
+      "WiFi": "https://raw.githubusercontent.com/ApolloAutomation/R_PRO-1/main/Integrations/ESPHome/R_PRO-1_W.yaml",
+      "Ethernet": "https://raw.githubusercontent.com/ApolloAutomation/R_PRO-1/main/Integrations/ESPHome/R_PRO-1_ETH.yaml"
+    }
+  }
+}
+```
+
+- Keyed by channel/variant so it aligns 1:1 with `firmware` and follows the same selection.
+- `config` (and any channel/variant within it) is optional. Missing => no section for that
+  selection.
+- Alternative considered and rejected: making each variant an object `{manifest, config}`.
+  That is a breaking change to all firmware-string handling and tests for no real benefit.
+
+Rationale for **raw** URLs (`raw.githubusercontent.com`): fetchable cross-origin
+(`Access-Control-Allow-Origin: *`, verified 2026-07-09) and directly downloadable as text.
+The GitHub blob "View on GitHub" URL is **derived** from the raw URL, so we store one field.
+
+## UI / behavior
+
+Placement: a collapsible block in **step 1** (below the release notes), because it is tied to
+the firmware/variant chosen there. It re-renders whenever the channel or variant changes.
+
+When the selected variant has a `config` URL:
+
+- **Summary/heading** framed as reflash/rebuild, e.g. "Build or reflash this firmware
+  yourself", with a one-line pointer to the device wiki.
+- **View** — on expand, fetch the raw YAML and render it in a `<pre><code>` block. The YAML
+  is runtime-fetched content, so it is escaped via the existing `esc()` before insertion
+  (per AGENTS.md security stance). Show a small "Loading…" then the content; on fetch failure,
+  show a short message plus the GitHub link (graceful, no throw).
+- **Download .yaml** — reuse the already-fetched text as a `Blob`, download with the real
+  filename derived from the URL path basename (e.g. `R_PRO-1_W.yaml`), sanitized. Using a
+  Blob avoids the cross-origin `download`-attribute limitation (a cross-origin `<a download>`
+  is ignored by browsers and would navigate instead of downloading).
+- **View on GitHub** — the blob URL derived from the raw URL
+  (`raw.githubusercontent.com/OWNER/REPO/BRANCH/PATH` -> `github.com/OWNER/REPO/blob/BRANCH/PATH`).
+
+When the selected variant has no config, the block is not rendered at all.
+
+## device.js refactor: one render epoch
+
+Adding a third async render (config fetch) is the moment to replace the three current ad-hoc
+staleness guards with a single mechanism, as flagged in the PR #1 review.
+
+- Introduce a per-`renderDevice` integer `epoch`, incremented whenever the channel or variant
+  changes (the seg click handlers).
+- Each async render (`renderInstall`'s manifest fetch, `renderReleaseNotes`, and the new
+  `renderConfig`) captures `const myEpoch = epoch` before awaiting and returns early if
+  `epoch !== myEpoch` after the await — i.e. the selection changed mid-fetch.
+- This replaces the existing `want` comparisons (`selectedManifest(...) !== want`,
+  `channel !== want`) with one consistent guard. The failure mode it protects against — a
+  stale fetch overwriting the current selection's firmware/config link — stays covered.
+
+## Deploy & security
+
+- **No new runtime file or directory** (no cache dir). `pages.yml` cp-list is unchanged.
+- Displayed YAML is escaped (`esc()`); the download filename is sanitized to a safe basename.
+- Blob content is the raw text (not inserted into the DOM), so it needs no escaping.
+
+## Validator
+
+Extend `scripts/validate_registry.py` so that, in addition to firmware manifests, every
+`config` URL is HEAD-checked (200). A broken config link then fails CI exactly like a broken
+manifest. The pure shape checks (a `config` entry, when present, is a string URL) are covered
+by the existing offline unit tests (`scripts/test_validate_registry.py`).
+
+## Tests (data-driven Playwright)
+
+All keyed off `devices.json`, no hardcoded ids:
+
+- A device that has a `config` for its default selection shows the section; a mocked raw fetch
+  renders the (escaped) YAML; the Download control and the derived GitHub blob link are present
+  and correct.
+- Variant switch updates the config: for a device whose variants have different config URLs
+  (R_PRO-1), selecting Ethernet shows the Ethernet config, WiFi shows the WiFi config.
+- Stale-fetch guard: a slow config fetch for a variant the user has switched away from must not
+  overwrite the current variant's section (exercises the new epoch), mirroring the existing
+  late-manifest tests.
+- A device with no `config` shows no section.
+
+## Registry population
+
+Probe each product repo to map the correct config file per variant (`_Factory.yaml` when
+present, else the main per-variant `<NAME>.yaml`), confirm each raw URL is reachable, and add
+the `config` entries to `devices.json`. Devices without a discoverable config are left without
+the field (no section). The `main` branch is used for the raw URLs unless a repo's default
+branch differs.
+
+## Out of scope / later
+
+- Caching configs into the repo (only worth it if raw fetch proves unreliable).
+- Showing the imported `Core.yaml` package contents inline (the entry/factory file references
+  it; users can follow the package URL). View shows the single selected file.
diff --git a/js/views/device.js b/js/views/device.js
index 4c7b37b..befd7a5 100644
--- a/js/views/device.js
+++ b/js/views/device.js
@@ -6,6 +6,22 @@ import { fetchReleaseNotes } from '../release-notes.js';
 const esc = (s) => String(s).replace(/[&<>"']/g,
   (c) => ({ '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;', "'": '&#39;' }[c]));
 
+function rawToBlob(raw) {
+  const m = raw.match(/^https:\/\/raw\.githubusercontent\.com\/([^/]+)\/([^/]+)\/([^/]+)\/(.+)$/);
+  return m ? `https://github.com/${m[1]}/${m[2]}/blob/${m[3]}/${m[4]}` : raw;
+}
+function configBasename(url) {
+  return (url.split('/').pop() || 'config.yaml').replace(/[^\w.\-]/g, '_');
+}
+function downloadText(text, filename) {
+  const blob = new Blob([text], { type: 'text/yaml' });
+  const url = URL.createObjectURL(blob);
+  const a = document.createElement('a');
+  a.href = url; a.download = filename;
+  document.body.appendChild(a); a.click(); a.remove();
+  setTimeout(() => URL.revokeObjectURL(url), 1000);
+}
+
 function selectedManifest(device, channel, variant) {
   return device.firmware[channel][variant];
 }
@@ -25,6 +41,7 @@ export function renderDevice(el, device) {
   const channels = Object.keys(device.firmware);
   let channel = channels.includes('stable') ? 'stable' : channels[0];
   let variant = Object.keys(device.firmware[channel])[0];
+  let epoch = 0; // bumps on every channel/variant change; async renders bail if it moved
   const hasSerial = !!navigator.serial;
 
   el.innerHTML = `
@@ -50,6 +67,7 @@ export function renderDevice(el, device) {
           <div id="variant-slot"></div>
         </div>
         <div id="release-slot"></div>
+        <div id="config-slot"></div>
         ${channels.length < 2 && Object.keys(device.firmware[channel]).length < 2
           ? '<p style="color:var(--dim);margin:0;">One firmware for this device — nothing to choose here.</p>' : ''}
       </section>
@@ -86,16 +104,19 @@ export function renderDevice(el, device) {
       const b = e.target.closest('button[data-variant]');
       if (!b) return;
       variant = b.dataset.variant;
+      epoch++;
       seg.querySelectorAll('button').forEach((x) => {
         const on = x === b;
         x.classList.toggle('active', on);
         x.setAttribute('aria-pressed', String(on));
       });
       renderInstall();
+      renderConfig();
     });
   }
 
   async function renderInstall() {
+    const myEpoch = epoch;
     const manifest = selectedManifest(device, channel, variant);
     if (hasSerial) {
       installSlot.innerHTML = `
@@ -116,7 +137,6 @@ export function renderDevice(el, device) {
             <li>Or use the <a href="${device.githubPagesInstaller}">classic installer page</a> in Chrome/Edge.</li>
           </ul>
         </div>`;
-      const want = manifest;
       // Pin the list element before the fetch: if the user navigates to another
       // device mid-fetch, the stale write lands on this detached node harmlessly
       // instead of the new device's freshly rendered #fallback-files.
@@ -125,12 +145,12 @@ export function renderDevice(el, device) {
         const res = await fetch(manifest);
         if (!res.ok) throw new Error('HTTP ' + res.status);
         const m = await res.json();
-        if (selectedManifest(device, channel, variant) !== want) return; // stale fetch — selection changed
+        if (epoch !== myEpoch) return; // selection changed mid-fetch
         const files = m.builds.flatMap((b) => b.parts.map((p) => new URL(p.path, manifest).href));
         filesEl.innerHTML =
           files.map((f) => `<li><a href="${encodeURI(f)}">${f.split('/').pop().replace(/[<>&"']/g, '')}</a></li>`).join('');
       } catch {
-        if (selectedManifest(device, channel, variant) !== want) return; // stale fetch — selection changed
+        if (epoch !== myEpoch) return; // selection changed mid-fetch
         filesEl.innerHTML =
           `<li>Couldn't load the file list — download firmware from the
              <a href="https://github.com/${device.repo}/releases">latest release</a>.</li>`;
@@ -141,10 +161,10 @@ export function renderDevice(el, device) {
   async function renderReleaseNotes() {
     const slot = el.querySelector('#release-slot');
     slot.innerHTML = '';
-    const want = channel; // discard the response if the channel changed by resolution time
+    const myEpoch = epoch;
     try {
       const rel = await fetchReleaseNotes(device.repo, channel);
-      if (channel !== want) return; // stale fetch — channel changed
+      if (epoch !== myEpoch) return; // selection changed mid-fetch
       const url = /^https:\/\/github\.com\//.test(rel.url) ? rel.url : `https://github.com/${device.repo}/releases`;
       slot.innerHTML = `
         <div class="release-notes">
@@ -155,7 +175,7 @@ export function renderDevice(el, device) {
           </details>
         </div>`;
     } catch {
-      if (channel !== want) return; // stale fetch — channel changed
+      if (epoch !== myEpoch) return; // selection changed mid-fetch
       slot.innerHTML = `
         <div class="release-notes">
           See <a class="fail-link" href="https://github.com/${device.repo}/releases">recent releases</a>
@@ -164,12 +184,47 @@ export function renderDevice(el, device) {
     }
   }
 
+  async function renderConfig() {
+    const slot = el.querySelector('#config-slot');
+    const url = device.config && device.config[channel] && device.config[channel][variant];
+    if (!url) { slot.innerHTML = ''; return; }
+    const filename = configBasename(url);
+    slot.innerHTML = `
+      <details class="config">
+        <summary>Build or reflash this firmware yourself</summary>
+        <p class="config-hint">The ESPHome config for the <strong>${variant}</strong> variant
+          (<code>${filename}</code>). Rebuilding from this keeps the device's onboarding, so the
+          <a href="${device.wiki}">${device.name} wiki</a> setup steps still apply.</p>
+        <pre class="config-yaml"><code>Loading config…</code></pre>
+        <div class="config-actions">
+          <button class="config-download" disabled>Download .yaml</button>
+          <a class="config-github" href="${rawToBlob(url)}" target="_blank" rel="noopener">View on GitHub →</a>
+        </div>
+      </details>`;
+    const codeEl = slot.querySelector('.config-yaml code');
+    const dlBtn = slot.querySelector('.config-download');
+    const myEpoch = epoch;
+    try {
+      const res = await fetch(url);
+      if (!res.ok) throw new Error('HTTP ' + res.status);
+      const text = await res.text();
+      if (epoch !== myEpoch) return; // selection changed mid-fetch
+      codeEl.textContent = text; // textContent escapes the runtime-fetched YAML
+      dlBtn.disabled = false;
+      dlBtn.addEventListener('click', () => downloadText(text, filename));
+    } catch {
+      if (epoch !== myEpoch) return;
+      codeEl.textContent = 'Could not load the config here — use "View on GitHub".';
+    }
+  }
+
   const chanSeg = el.querySelector('#channel-seg');
   if (chanSeg) chanSeg.addEventListener('click', (e) => {
     const b = e.target.closest('button[data-channel]');
     if (!b) return;
     channel = b.dataset.channel;
     variant = Object.keys(device.firmware[channel])[0];
+    epoch++;
     chanSeg.querySelectorAll('button').forEach((x) => {
       const on = x === b;
       x.classList.toggle('active', on);
@@ -178,9 +233,11 @@ export function renderDevice(el, device) {
     renderVariantSeg();
     renderInstall();
     renderReleaseNotes();
+    renderConfig();
   });
 
   renderVariantSeg();
   renderInstall();
   renderReleaseNotes();
+  renderConfig();
 }
diff --git a/scripts/test_validate_registry.py b/scripts/test_validate_registry.py
index 3023f0e..656581a 100644
--- a/scripts/test_validate_registry.py
+++ b/scripts/test_validate_registry.py
@@ -66,5 +66,31 @@ def test_read_phase_timeout_returns_false(self):
             self.assertFalse(vr.head_ok("https://example.com/x.bin"))
 
 
+class ConfigShape(unittest.TestCase):
+    def test_good_config_has_no_errors(self):
+        cfg = {"stable": {"WiFi": "https://raw.githubusercontent.com/o/r/main/a.yaml"}}
+        self.assertEqual(vr.check_config_shape(cfg, "r-pro-1"), [])
+
+    def test_non_string_url_errors(self):
+        cfg = {"stable": {"WiFi": 123}}
+        errs = vr.check_config_shape(cfg, "r-pro-1")
+        self.assertTrue(any("WiFi" in e for e in errs), errs)
+
+    def test_non_https_url_errors(self):
+        cfg = {"stable": {"Standard": "http://insecure/a.yaml"}}
+        errs = vr.check_config_shape(cfg, "x")
+        self.assertTrue(any("https" in e for e in errs), errs)
+
+    def test_channel_not_object_errors(self):
+        cfg = {"stable": "oops"}
+        errs = vr.check_config_shape(cfg, "x")
+        self.assertTrue(any("stable" in e for e in errs), errs)
+
+    def test_non_dict_config_errors_without_crashing(self):
+        for bad in (None, "oops", []):
+            errs = vr.check_config_shape(bad, "x")
+            self.assertTrue(any("config" in e for e in errs), (bad, errs))
+
+
 if __name__ == "__main__":
     unittest.main()
diff --git a/scripts/validate_registry.py b/scripts/validate_registry.py
index cea1351..16eb409 100644
--- a/scripts/validate_registry.py
+++ b/scripts/validate_registry.py
@@ -49,6 +49,24 @@ def check_manifest_shape(manifest, where):
                 errs.append(f"{where}: firmware part missing 'path'")
     return errs
 
+def check_config_shape(config, dev_id):
+    """Validate the optional `config` map (channel -> variant -> https URL).
+
+    Returns a list of error strings (empty when sound). Network-free.
+    """
+    errs = []
+    if not isinstance(config, dict):
+        errs.append(f"{dev_id} config: not an object")
+        return errs
+    for channel, variants in config.items():
+        if not isinstance(variants, dict):
+            errs.append(f"{dev_id} config {channel}: not an object")
+            continue
+        for variant, url in variants.items():
+            if not isinstance(url, str) or not url.startswith("https://"):
+                errs.append(f"{dev_id} config {channel}/{variant}: not an https URL")
+    return errs
+
 def check_manifest(dev_id, channel, variant, murl):
     where = f"{dev_id} {channel}/{variant}"
     try:
@@ -77,6 +95,16 @@ def main():
         for channel, variants in dev.get("firmware", {}).items():
             for variant, murl in variants.items():
                 check_manifest(dev["id"], channel, variant, murl)
+        config = dev.get("config", {})
+        errors.extend(check_config_shape(config, dev["id"]))
+        if not isinstance(config, dict):
+            continue
+        for channel, variants in config.items():
+            if not isinstance(variants, dict):
+                continue
+            for variant, curl in variants.items():
+                if isinstance(curl, str) and not head_ok(curl):
+                    errors.append(f"{dev['id']} config {channel}/{variant}: unreachable: {curl}")
     if errors:
         print(f"FAILED — {len(errors)} problem(s):")
         for e in errors:
diff --git a/tests/installer.spec.js b/tests/installer.spec.js
index e7cb377..f15d4b2 100644
--- a/tests/installer.spec.js
+++ b/tests/installer.spec.js
@@ -191,3 +191,77 @@ test('step 3 explains taking control in the ESPHome Dashboard', async ({ page })
   await expect(done).toContainText('Take control');
   await expect(done.locator('code')).toContainText('dashboard_import');
 });
+
+function blobFromRaw(raw) {
+  const m = raw.match(/^https:\/\/raw\.githubusercontent\.com\/([^/]+)\/([^/]+)\/([^/]+)\/(.+)$/);
+  return `https://github.com/${m[1]}/${m[2]}/blob/${m[3]}/${m[4]}`;
+}
+function defaultSel(d) {
+  const channels = Object.keys(d.firmware);
+  const channel = channels.includes('stable') ? 'stable' : channels[0];
+  const variant = Object.keys(d.firmware[channel])[0];
+  return { channel, variant, url: d.config && d.config[channel] && d.config[channel][variant] };
+}
+
+test('device config: reflash section renders the fetched YAML and derived GitHub link', async ({ page }) => {
+  const d = registry.devices.find((x) => x.config && defaultSel(x).url);
+  test.skip(!d, 'no device has a config for its default selection');
+  const { url } = defaultSel(d);
+  await page.route(url, (route) => route.fulfill({ contentType: 'text/plain', body: 'esphome:\n  name: mock-cfg\n' }));
+  await page.goto(`/#/${d.id}`);
+  await expect(page.locator('.config')).toBeVisible();
+  await expect(page.locator('.config-yaml code')).toContainText('mock-cfg');
+  await expect(page.locator('.config-github')).toHaveAttribute('href', blobFromRaw(url));
+});
+
+test('device config: switching variant swaps the config', async ({ page }) => {
+  const d = registry.devices.find((x) => x.config && x.config.stable && Object.keys(x.config.stable).length > 1);
+  test.skip(!d, 'no multi-variant config device');
+  const variants = Object.keys(d.config.stable);
+  for (const v of variants) {
+    await page.route(d.config.stable[v], (route) =>
+      route.fulfill({ contentType: 'text/plain', body: `esphome:\n  name: cfg-${v}\n` }));
+  }
+  await page.goto(`/#/${d.id}`);
+  await expect(page.locator('.config-yaml code')).toContainText(`cfg-${variants[0]}`);
+  await page.locator(`#variant-seg button[data-variant="${variants[1]}"]`).click();
+  await expect(page.locator('.config-yaml code')).toContainText(`cfg-${variants[1]}`);
+});
+
+test('device config: a slow fetch for a deselected variant does not overwrite', async ({ page }) => {
+  const d = registry.devices.find((x) => x.config && x.config.stable && Object.keys(x.config.stable).length > 1);
+  test.skip(!d, 'no multi-variant config device');
+  const variants = Object.keys(d.config.stable);
+  await page.route(d.config.stable[variants[0]], async (route) => {
+    await new Promise((r) => setTimeout(r, 1500));
+    await route.fulfill({ contentType: 'text/plain', body: 'esphome:\n  name: cfg-slow-0\n' });
+  });
+  await page.route(d.config.stable[variants[1]], (route) =>
+    route.fulfill({ contentType: 'text/plain', body: 'esphome:\n  name: cfg-fast-1\n' }));
+  await page.goto(`/#/${d.id}`);
+  await page.locator(`#variant-seg button[data-variant="${variants[1]}"]`).click();
+  await page.waitForTimeout(2500);
+  await expect(page.locator('.config-yaml code')).toContainText('cfg-fast-1');
+  await expect(page.locator('.config-yaml code')).not.toContainText('cfg-slow-0');
+});
+
+test('device config: download uses the real filename', async ({ page }) => {
+  const d = registry.devices.find((x) => x.config && defaultSel(x).url);
+  test.skip(!d, 'no device has a config for its default selection');
+  const { url } = defaultSel(d);
+  await page.route(url, (route) => route.fulfill({ contentType: 'text/plain', body: 'esphome:\n' }));
+  await page.goto(`/#/${d.id}`);
+  await page.locator('.config summary').click(); // expand so the button is visible
+  const [download] = await Promise.all([
+    page.waitForEvent('download'),
+    page.locator('.config-download').click(),
+  ]);
+  expect(download.suggestedFilename()).toBe(url.split('/').pop());
+});
+
+test('device config: no section when the device has no config', async ({ page }) => {
+  const d = registry.devices.find((x) => !x.config);
+  test.skip(!d, 'every device has a config');
+  await page.goto(`/#/${d.id}`);
+  await expect(page.locator('.config')).toHaveCount(0);
+});