If you go to https://jenkins.example.com/about/ , it reports what version of Jenkins is running, and the next section is:
|Jenkins war||org.jenkins-ci.main:jenkins-war:2.243||The MIT license|
|HttpCommons Client library||commons-httpclient:commons-httpclient:3.1-jenkins-1||Apache License 2.0|
|JUnit||junit:junit:4.13||Eclipse Public License 1.0|
As you can see, the links to "Jenkins war" and "HttpCommons Client library" are broken, but the JUnit one is fine. I only spot-checked a few more, but Jenkins remoting layer has a broken link, and probably a bunch more.
Not a blocker, but not sure why it broke.