I don’t like the default tabs behavior in Firefox. I hate to use the arrows to find not visible tabs. I prefer to see all open tabs although the tab is reduced with each new tab open. If I need to find a tab between many, I just move the cursor over each tab.
Well, there is a extension to this. The name is Prevent Tab Overflow, but for me is All Tabs Visible. I tested it and it works fine.
Yes, I’m a former Chrome user.
Regards