This is a benign Let's encrypt domain. The URL categorization has been cleared.
There was an issue that was resolved in 9.0.10-h2, 9.1.6, and 10.0.2, that caused URL's previously in a malicious category to get 'stuck' in that malicious category in the Firewall's DP Cache. See https://knowledgebase.paloaltonetworks.com/KCSArticleDetail?id=kA14u000000HCgjCAG If you are running a PAN-OS version that is higher than the ones mentioned above, and you see the URL categorization stuck in a malicious category, even after it being cleared out to be Benign (verifiable in Test-A-Site), please open a Support case to have the issue investigated for root cause.
... View more