Same Problem. had problems with notifications since a few days. now i wantet to add an Panel to my twitch side and this doesnt work. in edge, no problem. kick, no problem. so it must be a problem between opera and twitch. after i deleted my complett cache and cookies, i was loged out from twitch and cant login bcause of "not supportet browser".
had no problems for years now with opera und opera gx and now this hard thing ^^" fix this pls ^^"

@yaboimadman after clearing browser cache, it worked again

Same Problem. had problems with notifications since a few days. now i wantet to add an Panel to my twitch side and this doesnt work. in edge, no problem. kick, no problem. so it must be a problem between opera and twitch. after i deleted my complett cache and cookies, i was loged out from twitch and cant login bcause of "not supportet browser".
had no problems for years now with opera und opera gx and now this hard thing ^^" fix this pls ^^"