Obscure, hard to find settings. I try and click a small thumbnail view, and if I hit the tiny X in one corner, the channel I am paying a sub for is hidden, and finding the option to undo that one misclick is hidden, I looked for a half hour and nothing said a thing about where it was. On top of that, every time I have it installed Twitch lags and stalls out. I have 64GB of ram, that's just stupid.

no longer works :(

Es funktioniert einfach nicht.

wont let me save my blacklist after importing JSON file.

A lot of time investment for nothing. Added a lot of filters until the addon told me to restart firefox, because the settings could not be syncronized. After the restart EVERY SETTING WAS GONE! Wow! Hours of filtering all the crap out of twitch gone. So this addon is useless for people who actually use it. Great! Thanks for the hours wasted I invested in searching for tags, games, channels and so on.
Edit 2022-09-28:
Thanks for the reply. I gave it another chance and did exactly that. "reliable enough" is far beyond driven, considering that the locally saved settings should have priority over NULL cloud saved setting, isn't it?
BTW: this addon really could use a language filter, a positive list for languages.

I was using it for half an year.

I just found out clicking the X button often hides some other accounts as well, and there could be still some pages where the contents supposed to be filtered will still appear (eg go to `directory/game/GAME_NAME/videos/all` then change the Sort By to Recently Published).

Since the filter items are all shown in a letter order, there's no way I could find and revert hiding on those I didn't meant to. But even if it can show the chronological order, it's gonna be so much burden at this point with several hundreds of items for each hiding options.

It was good to have a "SEEMINGLY" solid way to completely hide not just categories but also channels on twitch, but now I can't trust the extension anymore. Even if I swallow the bitter pill and decide it's okay to ignore those innocent but wrongly hidden channels, I'd still gonna see some accounts and other things I actually wanted to never see ever again.

I liked this extension. I am going back to FFZ with only category-wise filtering.

Disabled all other extensions, refreshed page, restarted browser a few times, refreshed page a few more time, etc... It didn't load a single time.