I really can't see how this happens. I know what kind of information is sent to the v1/panopticon/admintools/scans endpoint (either none, or the start point for paginated data), and that it can't be blocked by the .htaccess file. Regardless, I did create a test site with all .htaccess options enabled and still couldn't reproduce the problem you have.
Moreover, that endpoint is only involved in running the PHP File Change Scanner. It is not involved with connecting the site to Panopticon. The core and extensions information is pulled from two completely different endpoints. If those were blocked, the rule you added would have not made any practical difference.
I can't help but thinking that maybe you misdiagnosed the issue and whatever the root cause was stopped being the case around the time you added the .htaccess rule, essentially creating a placebo effect.
Nicholas K. Dionysopoulos
Lead Developer and Director
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