Since upgrading to version 0.4.4, I’ve been having problems where sometimes the Twitter-friendly link works, but sometimes it ends up redirecting from http://example.com/1234 to http://example.com/1234/ (with a slash at the end) and bringing up a no-posts-found error instead of redirecting to the original page.
It seems to be a conflict with WP Super Cache. If it’s on or half-on, the first visit to the short URL works but subsequent ones don’t. If it’s off, the short URL works fine.
It’s worth noting that I’ve been using both plugins for months, and it’s only since upgrading Twitter Friendly Lings yesterday that I’ve seen the problem.
First, I tried rolling back to Twitter Friendly Links 0.4.3 and re-enabling WP Super Cache, and it appeared to work normally again.
Second, I think I’ve found a workaround for the problem. I’ve upgraded back to 0.4.4, and added the following line to the list of URL strings that WP Super Cache will avoid caching:
I’m just using the numeric short link with no prefix, so this ends up matching it with or without a trailing slash. People with different patterns for the short link will need different patterns to match here.
I think it’s a WP Super Cache issue, but I’ve been able to solve that the exact method you were trying to. Anyways, we’ve got an upcoming version of Twitter Friendly Links which will work via .htaccess by-passing any caching plugins, that should raise compatibility.