The rationale is explained here: https://bugzilla.mozilla.org/show_bug.cgi?id=928128#c11

1/ forbid users to enter links at all (text or markup), at the form submission level
2/ if, for some weird reason, the link still goes through, remove it when storing into the DB (that's the part you're commenting)
3/ when displaying the content (for some descriptions that were saved before this PR), just display the link inner text (if it's markup) or the link itself (if it's only text)