Firefox - How can I change window/site minimum width or disable it to make it flexible?

I'm currently trying to switch browser from Chrome to Firefox. But currently, there is a problem with Firefox where the window/site width size is not as flexible as Chrome window/site width size. On chrome, I can make the site have width as small as possible without cutting the view, while in Firefox it just cuts at certain width. *The website width is currently being cut unlike on Chrome* I have tried multiple things such as using userChrome.css advice from multiple Firefox forum but it still doesn't work. I tried to look for default/full sample of userChrome.css file or the entire documentation that may show some pointers about site min-width but I still couldn't find it(You can share the full documentation link if possible, that will help me a lot).