I'm having the same issue I'm on firefox, on macos. Here is what the problem looks like.
Hi @PXshadow, thank you for the information. I have installed Firefox and tried it, but it still fills the screen as expected for me. If it's not too much trouble, could you try in icognito/private mode, or with extensions disabled? I wonder if a privacy tool is stopping Heaps from getting the window size properly.