Youtube has two settings that must be turned on for captions to show and start automatically when watching a video. "Always Show Captions" and "Auto Play Captions" and not be forced to be signed in to YT. Both settings must be checked off/turned on for captions to work and "set" in the cookies, for captions to work when not signed into YT. Previously, one could sign in to YT, re-select the settings, refresh browser and then sign out and the captions would work when signed out and viewing YT content. Since your update today, YT's "auto play captions" option is now missing when using Firefox, but not when using chrome, meaning when using Firefox, it can't be selected while using that browser. The result is that persons who choose to use Firefox instead and don't want to be signed in to youtube, not wanting our information followed in a non anonymous manner, can't use firefox to watch YT and still have captions working without having to constantly turn them on for every single video watched (that's where "auto play captions" came in). Bad, bad move. On both mozilla's part and YT's.