Using Ctrl+MMB to scroll between panels and tabs can be very handy, but its implementation is different between the various editors and windows in Blender.
- In the Sidebar of various editors, the behavior is the best: scrolling happens both if the mouse is hovering on the panel and if it’s hovering on the tab.
- In the Properties editor, scrolling happens if hovering on the panels, but not on the tabs.
- In the File Browser, in the panels on the left, scrolling happens only with the items of the specific panel you’re hovering on.
- In the Preferences editor (the worst), not only you can scroll only when hovering on items of the same “group”, similar to the file browser, but here you can’t even just hover on the other “groups” to scroll, you also have to click before.
- In other areas like the Toolbar, scrolling doesn’t happen at all.