The project feeds have duplicate values for the guid for items. This is not allowed according to the spec. and confuses RSS readers. For example, the feed for metaf2xml has 2 items with the guid .../support-requests/27/ (one for "created ticket" and one for "modified ticket") and 3 items with the guid .../bugs/6/ (one for "created ticket" and 2 for "modified ticket").
sorry, I didn't provide the feed URL. It's not fixed for (at least) /p/PROJECTNAME/activity/feed, maybe others as well. The guid for bug entries is just the URL for the bug, for downloads it's the download URL etc. This is not unique, bugs may get many items, files may be deleted and uploaded again etc.
It would also help some feed readers (e.g. older Thunderbird) to have the
<guid>
be the permalink too. https://bugzilla.mozilla.org/show_bug.cgi?id=541718We'd have to make sure not to update any existing feed data, otherwise rss feed readers would show lots of feed items as "new" if they are new guids.