An additional piece of information which might help in tracking down the problem. All of the Slashdot entries' target links appear to exactly mirror what is shown in my browser's address bar.

I had a reply and navigated to "Slashdot nodelet links broken". My address bar had 'https://www.perlmonks.org/?node_id=11154878'; all of the Slashdot entries' target links had the same.

I voted on the reply; the query string was lost as usual; my address bar changed to 'https://www.perlmonks.org/?'; all of the Slashdot entries' target links now had the same: 'https://www.perlmonks.org/?'.

I thought that might help in determining where the Slashdot target URLs were coming from.

[Aside: The reply mentioned was from hippo re "jobs.perl.org" and I upvoted it. :-)]