Mar 17 2021
Mar 9 2021
Alright. Created T276893 for it.
Mediawiki version: 1.35.1
Mar 8 2021
Might not be fully fixed: T276782
Re-opening since I am having exactly the same issue as described in the original ticket description.
Somehow didn't get any notifications about your kind reply.
Doesn't have to be HTML indeed.
Dec 14 2020
I don't think this was completed. Created add Widgets extension compatibility with $wgCSPHeader CSP Content Security Policy (T270095) for it.
Jun 8 2020
Mar 12 2019
Jan 9 2019
Mar 18 2015
The more professional ones most likely remove that header at some level.
Mar 17 2015
Which project is this about?