Embedded autoplay cannot be turned off

[SelfRef]

The case

I use Invidious instance with an account where autoplay is turned on in the settings, so when I open a video page in Invidious it starts playing (same as on YouTube).

I also have the Privacy Redirect extension on Firefox with Invidious Redirects enabled. The only changed option is Invidious Instance URL set to my instance. The option "Invidious automatically play video on load" is in default OFF state.

The issue

Privacy Redirect extension is replacing embedded YouTube videos on every site (which is expected) but it also makes play them automatically. This is a different behavior than YouTube where embedded videos are not played automatically.

While browsing sites like Reddit embedded Invidious videos start to play by itself, even before I ever see them which is annoying.

I turned off autoplay in Invidious account settings, and it still plays embedded videos automatically.

The solution

Allow to disable autoplaying embedded Invidious videos.

[SelfRef]

Apparently the instance config default_user_preferences.autoplay: false need to be set. Only then embedded videos are not played automatically, probably because embedded videos only use the default instance settings which are set globally for every instance. Unfortunately, it's not a solution at all, because then on Invidious instance autoplay isn't enabled by default.