It is no longer possible to scroll by dragging the background of a screen

A while ago (probably before the recent addition of accessibility features), it was possible to scroll the scrolling parts of a screen by clicking its background and dragging it up or down. This is now no longer possible – you can now only scroll by clicking the scrollbar at the right.

Some of the affected screens are: Controls, Statistics, Language, Resource Packs, world selection, server selection etc.