I'm working on an updated version of an existing plugin. In the readme.txt file, I'll be adding an entry to the "Upgrade Notice" section, which will show up in users' Plugins admin page when the new version gets released. I see from the official readme.txt format that this field is limited to 300 characters. My question is, are links allowed in this field? I would like to link to a forum post about the new version. I realize I could put a URL in the field in any case, but I was wondering if I could put a link in the field using the Markdown syntax and make the link clickable on the users' admin screen.
I haven't confirmed the behavior of the Plugins admin screen, but using the official readme.txt validator, I see that the validator has stripped away the link that I put into the Upgrade Notice section. Judging from that, it looks like the answer is no.