# Fix About Dialog & Reprocess Always Uses Low-Res

**Date**: 2026-09-22 16:07  
**Task**: Fix native About dialog duplication/icon + force reprocessing to always use low-res preview file

## Issues Addressed

### 1. Native About Dialog Still Showing (Duplicate Version)
**Problem**: The macOS menu "About" item still opened the native About panel (which shows duplicate version strings "v0.1.2 (0.1.2)") instead of the custom Svelte `AboutDialog`.

**Fix**: Replaced the `AboutMetadataBuilder`-based `.about()` menu item with a custom `MenuItemBuilder` that emits a Tauri event (`open-about`). The frontend listens for this event via `listen('open-about', ...)` in `App.svelte` and toggles `showAboutDialog = true`.

**Files changed**:
- `src-tauri/src/lib.rs` — Replaced `AboutMetadataBuilder` usage with `MenuItemBuilder` + `PredefinedMenuItem` for hide/show/quit. Added `.on_menu_event()` handler to emit `open-about` event.
- `src/App.svelte` — Added `import { listen } from '@tauri-apps/api/event'` and a `$effect` that listens for `open-about` and opens the custom dialog.

### 2. Broken Icon in About Dialog
**Problem**: The `<img src="/favicon.svg">` tag failed to load in the Tauri webview, showing a broken image placeholder.

**Fix**: Inlined the SVG directly into the `AboutDialog.svelte` component, eliminating the external file reference. Added `rx="90"` to the background rect for rounded-corner macOS icon styling.

**Files changed**:
- `src/lib/components/AboutDialog.svelte` — Replaced `<img>` tag with inline `<svg>`.

### 3. Reprocessing Uses Full-Resolution File (Performance)
**Problem**: `reprocessCurrentVideo()` used `session.activeVideoPath` which points to the HQ export file after upgrade. All ffmpeg analysis (waveform, keyframes, thumbnails) on the full-res file takes minutes instead of seconds.

**Fix**: `reprocessCurrentVideo()` now explicitly prefers `session.previewFilePath` for processing. If that equals the export file (or is null), it falls back to checking the disk cache for a low-res preview via `checkCachedDownload(title, 'preview')`. Only uses `activeVideoPath` as a last resort.

**Files changed**:
- `src/lib/stores/videoSession.svelte.ts` — Rewrote `reprocessCurrentVideo()` to resolve the low-res preview path before triggering processing.

## Verification
- `cargo check` — 0 errors, 0 warnings
- `cargo test` — 58 tests passed
- `svelte-check` — 0 errors, 0 warnings
- `ReadLints` — No linter errors

## Lessons Learned
- Tauri's `.about(Some(metadata))` on `SubmenuBuilder` always creates the *native* macOS About panel — there is no way to redirect it to a custom webview dialog. To intercept "About", you must use a regular `MenuItemBuilder` with `.on_menu_event()`.
- Inline SVGs in Svelte components are more reliable than `<img src="...">` references in Tauri webviews, where path resolution can differ between dev and production builds.
- When a session tracks both a preview and export file path, any function that runs ffmpeg analysis must explicitly resolve which path to use — defaulting to `activeVideoPath` is a footgun since that gets upgraded to HQ.