How do you get rid of Firefox's windows decorations in Linux? All I could find was for Windows, except one gnome-based extension which is known not to work reli

How do you get rid of Firefox's windows decorations in Linux? All I could find was for Windows, except one gnome-based extension which is known not to work reliably. Also, checking for updates when I start my browser is the worst possible time UI-wise. I start my browser when the site I want to visit is at my fingertips, and my working memory is fading as I am waiting for my computer. How do you customize this away? Sure, the bookmarks bar being always-visible or never-visible is a minor defect, but it is still worse than Chrome's show-in-new-tabs behavior. Showing menu bars and window decorations by default shows bad judgement, but indeed that wasn't the reason I couldn't stay with Firefox. It felt slower, had annoying wasteful window decorations, started with annoying extension version checks, and let bad web apps interfere with all my tabs. Do you have actual responses for my actual points besides "you didn't really try"?