I noticed this bug this week, it happens both on the app and browser (tried on Chrome)

Whenever you resize a map, it creates a copy with the desired dimensions

You can work on the new map but keyboard shortcuts no longer work until you manually go into the menu top-left and select "Save"

Shortcuts include "CTRL+S" to save, "G" to snap to grid and more

Once the map has been saved manually, then keyboard shortcuts are enabled again

I tried with different maps and the issue is consistent, always happens when resizing