[xmonad] Change the visibility of windows

[Daniel Trstenjak]

Hi,

is there a way to temporary change the visibility of windows?

Sometimes I want to temporary only see two windows of the workspace side
by side and afterwards switch back to see all windows.

Something like tagging the two windows and then switching to a layout
only displaying the tagged.

Perhaps even being able to tag windows from different workspaces might
be a nice feature.

Greetings,
Daniel