Installed:

SPPB 3.8.10 Helix Ulitmate v2.0.13 J4.3.2

Updated a few websites from previous versions without any issues.

Installed extensions/plugins: Only the important ones that are really needed like the ones from Akeeba.

Tested first local on Mamp Pro, then on Litespeed based servers. PHP version: 8.08

Tip: Have a subdomain with a testing site with about the same setup/installed plugins/extensions as the main sites you run. Can save you some of headaches.

Just for info..