Captionfy.io - Captionfy is a free Youtube community captions platform with a subtitles/captions editor that you can use to create captions for any public Youtube video.
PocketTube - Group YouTube subscriptions into YouTube folder. Video Deck for Youtube. Mark as watched videos. Filter YouTube video. Youtube mode
NekoCap - Video & Movies
Amara - Amara
Subtitles Downloader by Checksub - Sometimes you may want to export or edit the subtitling of Youtube videos that you have uploaded or that you're fans of.
YouTube Vanced - Vanced is a modded version of YouTube with many features such as adblocking and background playback