Troubleshooting

Likely cause: Missing or unhealthy JS runtime.

Fix: Open Settings → Diagnostics & Logs: js_runtime must read deno or quickjs. Re-run setup; on desktop check network access for the runtime fetch; on Android reinstall the full APK (contributor builds without bundled natives have no runtime).

Likely cause: Parallel fetching off, or a DASH/HLS source.

Fix: Enable aria2c on Wi-Fi and raise chunks (max 16). Note: DASH/HLS streams always use the native downloader by design — that is expected, not a bug.

Likely cause: Post-processing stage (merge / embed / chapters).

Fix: By design: streaming progress caps at 99% and only the terminal finished event reports 100%. Watch the live log for the post-processing stage instead of restarting.

Likely cause: Incomplete install — the APK on your device lacks bundled native binaries.

Fix: Reinstall the full APK from GitHub Releases (all variants ship FFmpeg inside — never copy library files around manually). Alternatively set a custom FFmpeg path in Settings if you maintain your own build.

Likely cause: Stale app version missing the completion-event fix.

Fix: Update to the latest release — completion events are now delivered reliably even when the app polls slowly. Then check the per-download log to confirm the file landed.

Likely cause: Empty SponsorBlock categories, or embedding order confusion.

Fix: Make sure at least one SponsorBlock category (sponsor, intro, outro…) is enabled — with none selected there is nothing to cut. The cutter order (subtitles → chapters → metadata) is automatic; just re-run the item.

Likely cause: Region restriction or IP throttling.

Fix: The error card says when a VPN helps — follow its hint. Alternatives: a proxy, geo-bypass, a sleep interval between requests, or cookie login for your region.

Likely cause: Expired or misplaced partial files.

Fix: Resume scans search both download roots recursively for .part files younger than 24h. Verify your download directory path in settings if partial files are stored elsewhere.

Likely cause: Embedding switched off.

Fix: Turn on subtitle embedding in settings and confirm FFmpeg reports healthy in Diagnostics.

Likely cause: Battery optimization killing the process.

Fix: Exempt Grablytic from battery optimization so the keep-alive service survives. Downloads degrade gracefully rather than crash, and resume on next launch.