What is going on with this browser it's broken

I tried to log into a known website. I put my password and username and press “sign in”. The website send the message back “undefined”. I tried with another browser, it work just fine. I tried deleting cache, still won’t work same problem it say “undefined”. I tried using privacy mode, still same problem. I tried bank mode and with bank mode it worked just fine. So it’s clearly the browser the problem.

Also, when i do a google search i sometime get a white page saying error occur of you have problem with google make a feedback. but I just open a new google page and try again and then it work.

After deleting all cache and cookie, i got disconnected from everywhere. so I tried login back in to other website. Then I came to a website “twitch” telling me that this browser I’m using is not supported. Not even mentioning all the other issues with this browser recently, i wouldn’t know what to start with. cant play browser game cuz too laggy, can’t use most website, can’t even log into some website, getting warning message about website that are not dangerous, getting horizontal stripes line on youtube video because of a extension and youtube video are extremly cpu demanding. The browser itself is using so much power.

idk what to do. I like some of the stuff here. but now i’m done

Note there is a specific sub-forum dedicated to Avast Secure Browser (assuming that is what you are having problems with) here: Avast Secure Browser - Avast Community