Roblox is probably only meant to work with Chromium-based browsers, which Firefox isn't.
Wrong, there's something wrong with my settings. Trying it on default Firefox works and also works if I use another profile. This isn't 2000s where Firefox had a completely different experience from Chromium.
You know what mate you could have put the above info into your original post to help those trying to help you. Instead of the way you just came across in your reply, whether or not you agree with the aid given just accept it with thanks.
Don't take it personally. They play Roblox after all.
I literally just replied normally, what's the problem with you?
Since you mention that it's a configuration issue, can you try using troubleshoot mode and test applying your changes one by one?
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