User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0
Steps to reproduce:
Some feeds deliver invalid XML, like <title>Bad & incorrect</title>.
As an effect, the feed may be in error for weeks until the publisher removes the faulty article. It would be good to make the feed reader more tolerant to bad XML.
Some technical detail:
The error console shows:
XML Parsing Error: not well-formed
Location: http://www. [snip]
Line Number 196, Column 24:
feeds: downloaded: updates disabled due to error, check the url - http://www. [snip] FeedUtils.jsm:1957:27
Apparently this is due to a request with type "text/xml" here: