Running Firefox 100.0 on Linux Mint 20.3 Mate 1.26 I've noticed that websites like my bank use a "sub window" that slides in from the right to display the running balances. Prior to version 100, this worked perfectly with dual scroll bars, one for the main window and one for the "sub" window. Now, with version 100, the "sub" window has no scroll bar. I can control the window by using the keyboard up/down arrows, but the scroll bar for the "sub" window is non existent. You cannot have access to my bank account, but you can duplicate the problem with Google. Simply search for say, a celebrity, click on one of the displayed images, and the window that displays on the right used to have it's own scroll bar, beside the bar that controlled the main window. Sub window scroll bar is now gone. It seems you folks violated one of the Cardinal Sins of Programming: IF IT AIN'T BROKE, DON'T FIX IT. Scroll bars worked great before, Not sure whose idea it was to "improve" them. Rolling a Firefox update backwards is a logistical nightmare. Is there a possibility of a fix coming out soon or are we to live with this as a "feature"??? Thanks for your time.