KDE & Plasma users

I had the sneaky suspicion that there would be a way to click on the vertical scroll bar and get Page Up/Down, like in Windows, in addition to the very useful Linux way. I found that in Firefox, Thunderbird and other applications right-clicking achieves that. But in KDE Plasma applications I get a menu with more options, which is powerful but less efficient when you only want to move up/down. In fact, the menu doesn't add much because you can easily jump to the top/bottom or scroll up/down easily anyway.

For consistency, is there a way to make all applications work like Firefox? That menu could be shown with middle-click (but I wouldn't mind losing it). Failing that, middle-click on the scroll bar of KDE Plasma applications could do a Page up/down.

I see in settings I can make KDE Plasma applications do Page Up/Down with left-click and jump to location with middle-click, but then that's different from Firefox etc and muscle memory gets messed up.