Formatting was configured but never enforced: `bun run format:check`
reported 199 unformatted files and ran in no workflow and in no git hook,
so .prettierrc (printWidth 100, trailing commas) described an intention
rather than the tree.
This is the one-time sweep that makes the check gateable. Whitespace and
token-reflow only -- no behavioural change: `bun run check` reports 0
errors and all 1053 frontend tests pass before and after.
Kept out of every other commit on purpose. A 199-file diff mixed with
real changes is unreviewable, and the next commit turns format:check
into a hard CI gate so this cannot silently accumulate again.
`app.security.csp` was `null`, so the webview ran with no Content-Security-Policy
at all: any script that reached the web layer would have inherited the whole IPC
surface. There is no known injection path today (one app-owned `{@html}`, no
`innerHTML`/`eval`), so this is defence in depth rather than a fix for an open
hole.
`script-src 'self'` is the restrictive half — Tauri nonces SvelteKit's inline
bootstrap script at build time, so no `'unsafe-inline'` is needed — together with
`object-src`/`frame-src 'none'` and `base-uri 'self'`. `img-src`/`media-src`/
`connect-src` cannot be restrictive: the Jellyfin origin is typed in by the user
at run time and is routinely plain http on a LAN, so they allow `http:`/`https:`.
That is a wide grant for data, but it still bars `file:`/`filesystem:` and does
not touch script execution. A run-time policy naming the server exactly was
rejected: Tauri derives the header from immutable config when it serves the HTML,
so it would mean rebuilding config and reloading the webview on every server
change. `style-src` keeps `'unsafe-inline'` because Svelte compiles `style="…"`
attributes into markup; `worker-src`/`media-src` keep `blob:` for hls.js's
demuxer worker and its MSE object URL; `ipc:`/`http://ipc.localhost` keeps
`invoke` working. `devCsp` mirrors it with the eval/inline/websocket allowances
Vite's dev server needs.
The asset-protocol scope narrows from `$APPDATA/**` — the storage root holding
the SQLite database and the encrypted-token fallback file — to
`$APPDATA/thumbnails/**`. Since DR-137 moved downloaded media to the loopback
media server, `imageCache` is the only `convertFileSrc` caller left.
Needs manual verification on both platforms: thumbnails, online HLS video and
offline downloaded video cannot be exercised headlessly.
dtourolle