Hello,
I have nearby the same requirement to solve, but unfortunately not 100%.
I want to call the close all routine as it is available in open tab at the beginning ot some of my tiddlers.
This is not cleaning the list of tiddlers listed in open
<$action-sendmessage $message="tm-close-all-tiddlers"/>
A lot of Text here
Is there another way available?

  So it’s always good to have backups.