I configured all settings to reserve the space for workshelf (see screenshot below) but it is still showing behind other app windows i.e., other app windows are covering shelf. Any ideas on how to fix this issue?

Thanks.

I think you might be confusing two different things: z-order (always on top) and reserved areas at the edges of the screen. If you want the Shelf to always appear above other windows no matter what, you set the z-order from 'Same as other windows' to 'Always on top'.

Reserving screen space, on the other hand, is a mechanism that prevents MAXIMIZED windows from overlapping the COLLAPSED shelf. A window can still overlap it if it is not maximized and you move it over the shelf.

You can, of course, use both mechanisms at the same time.

I did notice that when Microsoft changed the taskbar they apparently also made some changes to the reserve screen space mechanism in Windows 11, which results even on maximized windows sometimes being able to overlap the shelf. This is one of the reasons why I added a 'Reset Reserved Screen Space' internal command - add it to a dock or shelf and, when clicked on, it should - as the name implies - reset the reserved screen areas.

Thanks Jorge. I did notice that even maximized windows are covering/overlapping the shelf. I will try the reset reserved screen space setting.

Also, the reserved space is ONLY for a shelf that is COLLAPSED (i.e. so the tabs are always visible when collapsed even if you have maximized windows open) **and*** DOCKED to a screen edge.