Show preview when switching windows with ⌘+Tab The ⌘+Tab key combination switches between active and background windows on my MacOS on MBP.

When hitting this combination, a small preview of the selected window appears. Another hit on the Tab key while ⌘ is pressed previews and selects the next window. Releasing the ⌘ switches to the currently selected window.

Recently, this preview does not appear, so I can't efficiently switch to other windows using a key combination.

Any idea how to restore that preview, please?
Solved by rebooting. The preview appears correctly now.