I recently updated both Fanmode and this blog to WordPress 2.5 and to my exasperation had to update them again shortly afterwards, this time to version 2.5.1.

(An important security fix! Must upgrade! Or else the internet will explode!)

I then discovered a little quirk with both blogs. Listing categories with subcategories results in some posts being listed twice. Here’s a screencap of what I’m talking about.

It’s the exact same post with an identical permalink listed twice.

I checked both blogs and both have the same issue. The exasperating thing is there’s no real consistency; some categories display this quirk while others are fine, some posts are repeated and others are not.

The problem isn’t due to WordPress 2.5 or 2.5.1. The culprit is actually Sideblog, the WordPress plugin I’m using for my sideblog. I had upgraded the plugin on both my sites to the latest version, 5.1, when I updated to WordPress 2.5.1 and after testing things out, I’m convinced Sideblog 5.1 is causing the problem. It’s apparently a returning problem.

Anyway, I reverted to Sideblog 4.5 and things seem to be working fine now. I should probably pass a note to the plugin’s author.