Manifest V3 updates requiring plugins to change how they handle background tasks.
Playlist downloading often fails because YouTube serves high-resolution video and audio as separate streams (DASH/HLS), which simple browser plugins cannot merge on their own. 7 Best Video Downloader Extension Firefox Tools (2026) 03-Feb-2026 —
If the permission for googlevideo.com is missing, the plugin cannot access the actual video streams. Some plugins require you to manually add this domain in their settings page (look for “Allowed Domains”).
Browser plugins are inherently restricted by Firefox's security sandbox. For a permanent solution that never breaks, open-source desktop software is highly recommended. yt-dlp (Command-Line Power Utility) youtube playlist downloader firefox plugin fix
YouTube updates its layout and internal code structure constantly. These changes break the scraping scripts used by basic browser extensions. Additionally, Mozilla regularly updates Firefox's security protocols (like the transition to Manifest V3), which can restrict how extensions interact with external video streams. Step-by-Step Fixes for Firefox Extensions
Only do this if you understand the security risks of running an outdated extension.
If your plugin remains broken, the issue likely stems from a permanent API block. Switching to one of these highly-rated tools will get your playlist downloads working again. Video DownloadHelper (With CoApp) Manifest V3 updates requiring plugins to change how
and ensure your extension is on the latest version. Developers often release fixes within days of a YouTube breaking change [18, 19]. Disable Conflicts : Tools like Adblock Plus Enhancer for YouTube
Browser extensions are inherently limited by browser memory restrictions and security sandboxes. For downloading large playlists, external desktop tools are vastly superior, safer, and less prone to breaking. yt-dlp (Recommended)
Click . If an update is available, install it and restart Firefox. 2. Configure Firefox Enhanced Tracking Protection (ETP) Some plugins require you to manually add this
If your current plugin is permanently broken, these are currently highly rated for Firefox users: youtube features not working(like add to playlist comment)
An advanced user tool that often works when others fail, as it uses your own browser to generate download links. 4. When Plugins Fail: Powerful Alternatives