Thank you so much for testing! You mentioned caching of wp-admin so I unchecked caching of both wp-admin and logged-in users in the litespeed settings. Still saw the 403.
I use Cloudflare turnstile on my contact form. I don’t know what the correct file name is for spam link so I put /turnstile/v0/api.js. Still the 403.
I don’t know if this sheds any light for troubleshooting:
Recently I upgraded my site to have four times as much memory and CPU. Same host, different (shared) server. Before that I could not run the BPS Pre-Install/Setup Wizard (saw 503 error) but was able to save all changes in Litespeed including page=litespeed-page_optm. It makes no sense now that I can run the Wizard but not save changes on that one page.
I would greatly appreciate it if you could look at my site setup as suggested and have emailed you a login as advised.
Please let me know any problems with that as I have not done that before.
I have left out the above code you provided in both places for the purposes of investigation.
Thank you again for your time.
This link can be used up till now!