Dusting off an old thread...
I had the same question because as I was recently modifying a macro (Insert Text Into Restricted Field) I discovered that the Activate Clipboard History Switcher action is a toggle, not exclusively an activation of the Clipboard History Switcher. @peternlewis confirmed this observation.
In my macro, I want to open the Clipboard History Switcher (or leave it open if it's already open), so I use this:
If Then Else.kmactions (2.2 KB)
2025-04-30 UPDATE: For a simpler solution, see @Nige_S's post below.