Our forum was converted from phpBB, with the importer creating a big table of URL redirects to keep all the old links working, which was much appreciated.
That worked well for about a year but in the last few months or so we’ve noticed that the first time you click on a redirect URL, you sometimes get Discourse’s “oops! that page doesn’t exist” error page.
The weird thing is, the redirects are not missing or broken, they actually do work, if you click the browser’s Refresh button when on that error page. Once you’ve done that once, the redirect URL then works fine (at least on the same computer).
I couldn’t find any other threads about this so I wonder if it’s something that has gone wrong with our forum, or maybe a plugin we’re using. Or is this a known issue? Any idea how to debug it, or what might be causing it?
Those redirects are still important to us, even now, since we have some external links and also quite a few posts on the forum still use the old URLs to link to each other. (At least at the time, the importer converted links in posts to the new format, but only if a later post linked to an earlier post; some posts had links to posts newer them themselves via edits, which remained in the old URL format, since the importer could only create redirects to topics that had already been converted when converting each topic. Our FAQs section in particular has a lot of crosslinking.)