I have category which name is '51m series' (it has id 135). Why the expression is_category(51) is true on this category page? I think it should be false according to Wordpress Codex. Is it a bug? ...
This certainly looks like a bug to me. I put together the following code for you to test it on a fresh install. Basically, the code will add two sub categories under the "uncategorized" to achieve ...