UBlock Origin and the "Safest" tor browser setting

Whonix as a development design decision does not modify settings “inside” Tor Browser.

This was previously attempted and I consider the approach failed:
add Tor Browser first startup popup to ask whether security slider should be set to safest

Tor Browser by The Tor Project does not provide a stable API / environment variable or documentation on how to enable blocking of all scripts upon start of Tor Browser. Neither a ticket against Tor Project exists. And I doubt a ticket would result in progress as other ticket such as

are unfixed for a long time. So for this to happen, someone would have to submit a pull request to Tor Browser.

Related Whonix Tor Browser Essentials documentation:

Whonix ™ Tor Browser Differences