AeroFetch/ROADMAP.md

AeroFetch Roadmap — feature parity with Seal

AeroFetch is the Windows/Electron counterpart to Seal, the Android Material-You frontend for yt-dlp. The core loop (probe → format pick → queue → download → history) is already in place. This document tracks the remaining gap: everything Seal does that AeroFetch doesn't yet.

Sources: Seal GitHub · Seal on F-Droid · It's FOSS overview.

See also: ROADMAP-PINCHFLAT.md — a parallel track that extends AeroFetch from a one-shot downloader into a Pinchflat-style media manager (index entire channels → organize into Channel / Playlist / Title folders → keep in sync), reusing the existing queue/history/options rather than replacing them.

Post-parity work (YTDLnis-derived editing features + Windows-native/UX polish + reliability) is tracked at the end of this document under Post-parity (Phases L onward).

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Already at parity ✅

Video + audio download · audio → mp3 with embedded thumbnail/metadata · interactive format picker (probe) · quality presets · queue + concurrency cap + cancel · download history (open / show-in-folder) · clipboard auto-detect · light/dark theme · output folder + filename template · yt-dlp version check · NSIS installer + portable build.

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Phase A — Core download power ✅ COMPLETE

A shared DownloadOptions model (src/shared/ipc.ts) carries the post-processing choices end-to-end. Persisted defaults are editable in Settings → Format & post-processing via a reusable DownloadOptionsForm component, which the download bar also hosts in a collapsible per-download Options panel. The main process emits the flags in buildArgs (src/main/download.ts). All items verified in the UI preview (typecheck clean). Real-download smoke test ✅ (2026-06-23): crop-to-square cover, audio re-encode (opus), video container + codec preference (mkv + vp9 merge), subtitle embed (→ mov_text), chapter embed, and SponsorBlock-remove (output duration shrinks by the cut segments) are now all verified against live yt-dlp + ffmpeg in real-download.integration.test.ts. That pass found and fixed a real shipping bug — the bundled ffprobe.exe was missing (see CODE-AUDIT C1).

• Playlist downloads. Probe now uses yt-dlp -J --flat-playlist and returns either a single video (with formats) or a flat playlist. The download bar shows a selection panel (scrollable checkbox list, select-all/none, live count) and enqueues each chosen entry as its own single-video download — reusing the existing queue/concurrency/history.
• Subtitles. Download + embed (--write-subs, --write-auto-subs, --sub-langs, --embed-subs, --convert-subs srt); language field + auto-caption toggle.
• SponsorBlock. --sponsorblock-mark / --sponsorblock-remove with a category multi-select (sponsor, intro, outro, selfpromo, music_offtopic…) + --force-keyframes-at-cuts.
• More audio formats. Was mp3-only. Now best / mp3 / m4a / opus / flac / wav / aac via --audio-format.
• Video container + codec preference. Container choice (mp4/mkv/webm) + preferred codec (-S res,fps,vcodec:…) to nudge toward av1 / vp9 / h264 without overriding the requested resolution.
• Embed chapters. --embed-chapters toggle. (--split-chapters still TODO.)
• Embed thumbnail crop-to-square for audio (Seal's "crop artwork") via thumbnail post-processor args. Smoke-tested ✅: the embedded cover comes out a perfect square (360×360) — the --ppa crop recipe survives yt-dlp's shlex split + ffmpeg's filtergraph.
• Per-download overrides. Collapsible Options panel in the download bar (shared DownloadOptionsForm) so one download — or one playlist batch — can deviate from the persisted defaults; "Reset to defaults" clears it. Threads options through addFromUrl → DownloadItem → startDownload and is carried on retry.

Phase B — Access & networking ✅ COMPLETE

buildArgs's former NetworkOptions param is now AccessOptions (still in src/main/buildArgs.ts) — it grew past pure networking once cookies and filename/archive flags joined proxy/rate-limit/aria2c. Smoke-tested ✅ (2026-06-23): --restrict-filenames (spaces → underscores) and --download-archive (a second run of the same URL is skipped with no fresh download) are verified end-to-end. Still untested live: the sign-in window's cookie export — it needs an interactive login against a gated video, which can't run unattended, so it stays reasoning + typecheck only. aria2c (optional, binary not bundled) and proxy (needs a live proxy server) are likewise not smoke-tested.

• Cookies. Settings → Cookies has a source picker: - From a browser's cookie store → --cookies-from-browser <name> (chrome/edge/ firefox/brave/opera/vivaldi — COOKIE_BROWSERS in src/shared/ipc.ts). - Sign-in window (built into AeroFetch) → opens an Electron BrowserWindow on a persisted session partition (persist:aerofetch-login, see src/main/cookies.ts); OAuth/SSO popups are allowed through onto the same partition. Closing the window exports its cookies to a Netscape-format file (userData/cookies.txt) which buildArgs passes via --cookies. Settings → Cookies shows last-saved time + a "Clear saved cookies" button (also clears the partition's storage).
• aria2c external downloader. Settings → Network has a "Use aria2c downloader" toggle; when on and resources/bin/aria2c.exe exists, buildArgs emits --downloader <path> --downloader-args (ARIA2C_ARGS in src/main/buildArgs.ts: -x 16 -s 16 -k 1M). Missing binary falls back silently to yt-dlp's own downloader (checked in src/main/download.ts). Binary is optional and not committed — see resources/bin/README.md.
• Proxy (--proxy) and rate limit (--limit-rate). Settings → Network fields (Settings.proxy / Settings.rateLimit), threaded through buildArgs's AccessOptions param.
• Restrict filenames toggle (--restrict-filenames) + download archive (--download-archive, skip already-downloaded) — both in Settings → Filenames. The archive file lives at a fixed userData/download-archive.txt (getDownloadArchivePath() in src/main/settings.ts), not user-configurable.

Phase C — Custom commands & yt-dlp management ✅ COMPLETE

Named CommandTemplates (src/shared/ipc.ts) persist to templates.json (src/main/templates.ts, mirrors history.ts's plain-JSON pattern) and are managed inline in Settings → Custom commands via TemplateManager.tsx — no modal, matching the rest of the app's no-portal-overlay convention (see the Hint/Select comments re: this dev machine's GPU/driver). A template's extra yt-dlp flags are shell-split (parseExtraArgs, src/main/buildArgs.ts) and appended to the generated argv immediately before the -- URL terminator, so a template flag can override anything chosen earlier. Settings.customCommandEnabled + defaultTemplateId apply a template to every new download; the download bar's own Custom command panel lets a single download override that default or opt out entirely (extraArgs on StartDownloadOptions, mirroring the existing per-download options override). buildCommand() (src/main/download.ts) now centralises settings/access/ options/extraArgs resolution, shared by both the real startDownload spawn and the new preview path. All items verified in the UI preview + npm run typecheck + npm run test (11 new unit tests covering parseExtraArgs, formatCommandLine, and extraArgs ordering). Smoke-tested ✅ (2026-06-23): parseExtraArgs('--write-info-json --no-mtime') splits into discrete tokens and the flags reach a live yt-dlp run — the .info.json sidecar is written, confirming custom-command args take effect end-to-end.

• Custom command templates. Named, editable templates of extra yt-dlp args (CommandTemplate), CRUD'd inline via TemplateManager.tsx; persisted to templates.json. Pick a default via Settings.defaultTemplateId (a Select in the Custom commands card). The "run custom command" mode is Settings.customCommandEnabled, applied to every new download unless overridden per-download in the download bar's Custom command panel.
• Command preview. IpcChannels.commandPreview → previewCommand() (src/main/download.ts) builds the exact argv via the same buildCommand() path a real download would take, then renders it with formatCommandLine. Surfaced as a Preview command button in the download bar, with a Copy button.
• In-app yt-dlp updater. updateYtdlp(channel) (src/main/ytdlp.ts) runs yt-dlp's own --update-to stable|nightly. Surfaced in Settings → About, right next to the existing version check, with a channel picker + result output.

Phase D — Library, UX & notifications ✅ COMPLETE

History stays plain JSON (history.json, 500-entry cap) — search/filter/select are done client-side over the already-small array, so the planned better-sqlite3 migration wasn't needed for this phase and was deliberately skipped to avoid a native-module build step for no functional gain at this scale. Failed downloads (pre-spawn rejections and in-flight yt-dlp failures alike) now persist to a new errorlog.json (src/main/errorlog.ts, 200-entry cap) independent of the queue, so a report survives Clear finished. Native notifications and the backup file both reuse existing settings/templates plumbing (getSettings/setSettings, listTemplates/the new replaceTemplates) rather than adding parallel storage. All items verified in the UI preview (typecheck + npm run test clean).

• History search + multi-select + filter (video/audio) + bulk delete + re-download. HistoryView.tsx gained a search box, an All/Video/Audio filter, a "Select" mode with per-row checkboxes + select-all + Delete selected (new historyRemoveMany IPC, src/main/history.ts), and a per-row re-download button that re-queues the entry's URL/kind/quality via the existing addFromUrl.
• Native OS notifications on completion / failure (Electron Notification, src/main/download.ts). Gated by a new Notify when downloads finish switch (Settings.notifyOnComplete, default on); clicking a notification refocuses the window.
• Private / incognito mode — a download bar toggle (DownloadBar.tsx, sticky like an incognito tab) sets DownloadItem.incognito, which store/downloads.ts checks before ever calling useHistory().add(...). Queue items show an eye-off badge when private.
• Backup / restore settings + templates (export / import JSON). New src/main/backup.ts writes/reads { settings, templates } via a save/open dialog; replaceTemplates() (src/main/templates.ts) does a full restore rather than a merge-by-id. Surfaced as Settings → Backup & restore.
• Error log / copy error report view (Seal's debug report). New src/main/errorlog.ts persists every failure (pre-spawn rejection, spawn error, or non-zero yt-dlp exit); Settings → Diagnostics lists recent entries with Copy full report and Clear log.

Phase E — Theming & platform polish ✅ COMPLETE

Some items are Android-specific in Seal and adapted to Windows here.

• Theme presets + "follow system" and high-contrast. Settings → Appearance has a Theme select (Light / Dark / Follow system) and four accent presets — Toffee (original), Slate, Evergreen, Lavender — each a 16-stop BrandVariants ramp sharing toffee's lightness curve at a different hue (src/renderer/src/theme.ts). "Follow system" reads Electron's nativeTheme.shouldUseDarkColors in the main process (src/main/index.ts's resolveBackgroundMode/registerSystemThemeBridge, pushed to the renderer over a new system-theme:update channel into src/renderer/src/store/systemTheme.ts) so the native window background stays in sync too, not just the in-page theme. High contrast: nativeTheme.shouldUseHighContrastColors surfaces as a status row in Settings → Appearance with a shortcut to Windows' contrast settings (ms-settings:easeofaccess-highcontrast); actual color overrides are left to Chromium's native forced-colors handling since nothing in the app sets forced-color-adjust: none. The sidebar's quick toggle still works under "system" — it sets an explicit light/dark away from whatever's currently resolved, breaking out of auto. Verified in the UI preview (typecheck + npm run test clean): default Toffee, switching to Slate/Evergreen/Lavender, Light/Dark/Follow-system, and the sidebar toggle's break-out-of-system behavior all checked visually.

• Windows "open with" / share integration. Both mechanisms named above, since a Win32 (non-MSIX) app can't register as an actual Share Target: - aerofetch:// protocol (aerofetch://download?url=<encoded>) — registered at install time via electron-builder.yml's protocols field (NSIS), and at runtime via app.setAsDefaultProtocolClient in src/main/index.ts (covers the portable build and dev, which have no installer step to do it for them). - Explorer "Send to AeroFetch" — src/main/deeplink.ts's registerSendToShortcut() writes a .lnk into %APPDATA%\Microsoft\Windows\SendTo via Electron's shell.writeShortcutLink (no native deps). Sending a .url Internet Shortcut file (what Explorer/browsers create from "Create shortcut"/dragging a tab to the desktop) passes its path as argv; extractIncomingUrl() parses the URL= line.

  Both paths funnel through the same `extractIncomingUrl()` (only ever forwards http(s)
  targets — same restriction as the existing external-link window-open handler) and a new
  `external-url` IPC push channel. The renderer surfaces the incoming link via
  `DownloadBar.tsx`'s existing clipboard-suggestion banner (now labeled "Link received:"
  for this source instead of "Use copied link?") rather than a new UI element. Added
  `app.requestSingleInstanceLock()` + a `second-instance` handler so a second invocation
  (the OS relaunching us for the protocol/SendTo case) hands its link to the already-running
  window instead of opening a duplicate. `extractIncomingUrl()`'s parsing/validation logic
  has 10 new unit tests (`test/deeplink.test.ts`); typecheck and the full suite are clean.
  *Caveat: the OS-level wiring (protocol registration, second-instance routing, the SendTo
  shortcut) is main-process/Electron-only and can't be exercised in the Vite browser
  preview used elsewhere in this phase — worth a real install + a manual
  `aerofetch://download?url=...` / "Send to" smoke test, same spirit as Phases A–C's
  real-download caveats.*
  

• Onboarding / welcome screen on first run. Settings.hasCompletedOnboarding (default false, persisted) gates a full-screen Onboarding.tsx rendered in place of the sidebar + main content in App.tsx — not a Fluent Dialog, since this app avoids Fluent's portal-based overlays entirely (GPU/driver blank-overlay issue noted in src/main/index.ts and Select.tsx). Shows the brand mark, a one-line pitch, the download-folder picker (same field as Settings → Downloads), three tip bullets, and a "Get started" button that flips the flag. Gated on the settings store's loaded flag so a returning user's real settings can never get clobbered by a one-frame flash of the default-false state. Verified in the UI preview (typecheck + npm run test clean): screen renders, folder field/browse work, "Get started" dismisses into the normal app.

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Not portable from Seal (noted for completeness)

• SAF directory picker (Android storage) → already covered by the native folder dialog.
• Android share-sheet / quick-download-on-share → mapped to Phase E's aerofetch:// protocol
  • Explorer "Send to" integration (a true Share Target needs an MSIX package, out of scope for this app's NSIS/portable distribution).
• F-Droid distribution → N/A (AeroFetch ships NSIS + portable).

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Post-parity — editing, native polish & reliability

With both parity tracks complete — Seal (Phases A–E above) and the Pinchflat media-manager roadmap (Phases F–K ✅) — this final track collects what's left, from two sources:

1. A feature study of YTDLnis (the other major Android yt-dlp frontend), keeping only the features AeroFetch doesn't already have.
2. A Windows-native + daily-use UX gap analysis of AeroFetch itself (things neither Seal nor Pinchflat cover, but that a desktop app should do).

Nothing here is built yet — every box is unchecked. Phases continue the existing lettering (A–E Seal, F–K Pinchflat) from L onward, and each item carries the yt-dlp flag and the AeroFetch file it touches so it can be driven straight from the existing buildArgs / DownloadOptions / queue plumbing rather than new infrastructure.

Sources: YTDLnis GitHub · YTDLnis docs · YTDLnis changelogs · F-Droid listing.

Already at parity with YTDLnis (do not rebuild)

Format/quality/container picking · SponsorBlock (remove/mark + embed-as-chapters) · embed subtitles/metadata/chapters · cookies + login · custom command templates · backup/restore · Observe Sources (= our Phase J watched sources + RSS) · incognito mode · history with filter + bulk re-download · filename templating · self-managing yt-dlp + ffmpeg binaries. AeroFetch is even with, or ahead of, YTDLnis on all of these.

Phase L — Media editing (YTDLnis headline features)

YTDLnis's signature differentiator. The keyframe plumbing already exists in AeroFetch (--force-keyframes-at-cuts is emitted today for SponsorBlock-remove in src/main/buildArgs.ts), so this is cheaper than it looks.

• Trim / cut downloads. Keep only chosen time ranges (multiple allowed). → parseTrimSections (src/main/buildArgs.ts) normalises raw user text into yt-dlp --download-sections "*START-END" specs (+ --force-keyframes-at-cuts, deduped against SponsorBlock-remove). Threaded as StartDownloadOptions.trim through store/downloads.ts, surfaced as a collapsible Trim panel in DownloadBar.tsx (single downloads only). Implemented + unit-tested (buildArgs.test.ts — 7 new tests; typecheck + test green). Live smoke test pending, plus two follow-ups: timestamp-range only so far (chapter-based cuts via the probe chapters[] array, and a scrubber/preview player, still TODO).
• Split by chapters into separate files. → --split-chapters (already flagged as a TODO in Phase A above). One toggle on DownloadOptions + src/renderer/src/components/DownloadOptionsForm.tsx; pairs naturally with trim. yt-dlp keeps the full file and writes per-chapter files via its default chapter: template. Implemented + unit-tested (buildArgs.test.ts, typecheck + test green); live smoke test still pending.
• Metadata editing before download. Change title / author / artist pre-download (YTDLnis: "modify metadata such as title and author"). → --parse-metadata / --replace-in-metadata; fits the audio path. Good for building a clean music library where the source title is messy. Held: the exact set-a-literal recipe is fragile (--parse-metadata FROM:TO splits on a colon that titles often contain; --replace-in-metadata FIELD REGEX REPLACE has empty-field + regex-replacement edge cases) — confirm against a live yt-dlp run before wiring it, rather than guessing the flag.

Phase M — Queue & daily-use UX ✅ COMPLETE

Neither Seal nor Pinchflat covers these; they're what makes the queue pleasant to live in. Today src/renderer/src/store/downloads.ts has cancel + retry only.

• Pause / resume individual downloads. → yt-dlp resumes .part files via --continue (already the default). Done: pauseDownload() (src/main/download.ts) reuses the taskkill /T /F tree-kill via a new killTree helper but flags the record paused so the close/error handlers stay silent (no error event/log/notification); new download:pause IPC + preload bridge. Renderer pause/resume (store/downloads.ts) + a paused status: pause frees a concurrency slot, resume re-queues WITHOUT resetting progress so the relaunch continues the partial. Pause/Resume buttons + a frozen progress row in QueueItem.tsx; paused items survive "Clear finished". typecheck + test green; live resume-continues-the-.part still wants a smoke test.
• Reorder / prioritize the queue. Done as a "Download next" action rather than drag: since the queue renders newest-first while pump() promotes oldest-first, a reposition primitive is clearer than drag. prioritize(id) (store/downloads.ts) moves a queued item to the front of the promotion order; an up-arrow button on queued rows (QueueItem.tsx).
• Aggregate progress + total ETA + combined speed. A header strip on the Downloads view summing bytes/speed across active items. Feeds straight into Phase O's taskbar progress bar. Done: pure summarizeQueue (store/queueStats.ts) → a strip in DownloadsView.tsx (overall %, combined speed, longest-ETA "time left"); unit-tested (test/queueStats.test.ts). A true remaining-bytes combined ETA is still out of reach — we don't track per-item sizes — so "time left" is the longest single ETA.
• Drag-and-drop a link or .url file onto the window. Done: the download card (DownloadBar.tsx) handles onDragOver/onDrop with a dashed-outline drag highlight, accepting text/uri-list/text/plain (firstUrl) and dropped Windows .url Internet-Shortcut files (parseUrlFile, read via File.text()); both http(s)-validated by the existing looksLikeUrl. A dropped link fills the URL field.
• Retry all failed. One action that re-enqueues every failed item. Done: retryAll() in store/downloads.ts re-queues all error items + a "Retry all failed (N)" button in DownloadsView.tsx. (Re-queues live queue items rather than reading errorlog.json — same effect for the on-screen failures.)
• Duplicate detection. Warn ("you already have this") before enqueuing a URL already in the active queue. Done: pure sameVideo() (store/queueStats.ts, YouTube-id aware + normalised-URL fallback) drives a "Already in your queue — Download anyway?" banner in DownloadBar.tsx; unit-tested. Checks the live queue (which still holds recently-completed items); cross-checking history.json for older downloads is a possible extension.
• Per-download scheduling + "save for later." Done: a saved status + optional scheduledFor (store/downloads.ts); pump() ignores saved (the time gate), and a 15s ticker promotes due scheduled items to queued. UI: a Schedule panel with a native datetime-local input in DownloadBar.tsx (future time parks the new download as scheduled), plus per-row Save for later / Add to queue actions in QueueItem.tsx; saved items survive "Clear finished". Distinct from the Phase J --sync schedule (which is for sources). Limitation: the queue isn't persisted, so a schedule only fires while AeroFetch is running — noted in the UI hint and the code.

Phase N — Power-user surface ✅ COMPLETE

YTDLnis leans hard into this; AeroFetch had the building blocks (command preview, templates, per-item options) but not the surfaces. typecheck + test + npm run build clean.

• Built-in terminal mode. Done: src/main/terminal.ts runs the bundled yt-dlp with raw user args (binary fixed; gated on customCommandEnabled, enforced in main), streaming stdout/stderr line-by-line over a new terminal:output channel (terminal:run/cancel IPC + preload). New TerminalView.tsx (args box, Run/Stop/Clear, live log, Ctrl+Enter) and a Terminal sidebar tab.
• Per-playlist-item editing. Done: the playlist panel in DownloadBar.tsx gained a per-row video/audio toggle + All video / All audio batch buttons; addPlaylist enqueues via addMany with each entry's own kind (quality falls back to that kind's default). Per-item exact-format selection (needs probing each entry) left as a further extension.
• Weighted format sorting ("format aspect importance"). Done: a formatSort field on DownloadOptions (raw yt-dlp -S string); when set it emits -S <value>, overriding the codec tiebreaker (buildArgs.ts); an "advanced" input in DownloadOptionsForm. Unit-tested.
• URL-regex template auto-matching. Done: CommandTemplate.urlPattern (regex); selectExtraArgs auto-applies a matching template ahead of the global default (matchesUrl, bad patterns never match), URL threaded via resolveExtraArgs. urlPattern field in TemplateManager + persisted in templates.ts. Unit-tested.
• Command palette + keyboard shortcuts. Done: a portal-free CommandPalette.tsx (filter, ↑/↓, Enter, Esc) opened with Ctrl/Cmd+K from App.tsx; actions = navigate tabs, new download (focuses the aerofetch-url input), toggle theme.

Phase O — Windows-native integration & discoverability

Grepping src/main confirms none of these exist yet (no setProgressBar, Tray, setThumbarButtons, setJumpList, globalShortcut). All live in the main process, mostly in src/main/index.ts.

• Taskbar progress bar. win.setProgressBar(fraction) driven by Phase M's aggregate progress. ~20 lines, very high perceived-quality return.
• System tray + minimize-to-tray. A Tray with show/quit/pause-all. This is also the coherent home for the watched-source background sync (Phase J), which today just "launches the normal window unobtrusively."
• Thumbnail toolbar buttons (win.setThumbarButtons) — pause/cancel from the taskbar preview — and a jump list (app.setJumpList) with "Paste & download."
• Taskbar overlay badge (win.setOverlayIcon) showing active-download count / error state.
• Settings discoverability. src/renderer/src/components/SettingsView.tsx is ~1,000 lines across ~10 cards. Add a settings search box or a Basic / Advanced split so first-time users aren't faced with the full power-user wall.

Phase P — Reliability, longevity & trust

The least glamorous, highest-leverage track: make sure what's already shipped actually works, keep YouTube downloads working as the platform tightens, and remove first-run friction.

• PO Token generation. YTDLnis mints YouTube tokens in a WebView to dodge throttling and "Sign in to confirm you're not a bot." This is becoming required for YouTube to keep working at all. → reuse the existing persisted Electron BrowserWindow (persist:aerofetch-login in src/main/cookies.ts) to host a token-minting script, or support a PO-token provider, passed via --extractor-args youtube:po_token=…. A longevity hedge more than a feature.
• Verify the shipped-but-untested OS wiring (flagged across both parity tracks as "reasoning + typecheck only"). A single real NSIS-install smoke-test pass over: the cookies sign-in window export · the aerofetch:// protocol + Explorer "Send to" · the scheduled --sync + RSS fast-check (Phase J) · aria2c · proxy. Converts a lot of "probably works" into "verified."
• Code signing. The unsigned .exe triggers SmartScreen "Run anyway" — the single biggest first-run friction for anyone you share it with. electron-builder win signing (OV/EV cert); EV builds SmartScreen reputation fastest.
• i18n / language setting. Carried over from Phase E (deferred). YTDLnis and Seal both ship many languages. Large but optional — needs an i18n library + string extraction, with translations arriving incrementally.

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Post-parity — what we reuse vs. build

Reuse unchanged: buildArgs/buildCommand flag emission, DownloadOptions + DownloadOptionsForm, the renderer queue scheduler + concurrency cap + per-item options, the persisted cookies BrowserWindow, the probe's chapters[]/format data, errorlog.ts, CommandTemplates, extractIncomingUrl(), and the self-managing binary updater.

Build new: the trim/split UI + --download-sections/--split-chapters wiring (L), the pause/reorder/schedule queue states (M), the terminal view + per-item playlist editor (N), the main-process taskbar/tray/jumplist integration (O), and the PO-token provider (P).

Post-parity — suggested order

L is the high-value headline — trim + split-chapters share one UI surface and the keyframe plumbing already exists, so they land cheaply and give AeroFetch YTDLnis's marquee capability. Then P's PO-token + verify-wiring as a reliability block (keeps YouTube working and de-risks shipped features). M and O are the daily-use polish and pair well (aggregate progress → taskbar bar). N is the power-user surface, each item independently shippable. Each phase is self-contained and rebuild-gated (npm run typecheck + npm run test + npm run build) the same way Phases A–K were.