Top Level Categories vs WP No Category Base for WordPress
I installed Top Level Categories yesterday, just to realize today that I should have taken the name literal TOP LEVEL CATEGORIES, as it throws 404 errors when trying to view the archive of any sub category… so Top Level Categories is really what it says: It makes categories be top level (no /category/ slug in front of the actual category slug) and there can't be any 2nd level categories… since I am using a lot of sub categories, I cannot use Top Level Categories.
WP No Category Base works perfectly for my needs, it removes the /category/ slug and still allows for sub categories.
So, in case you were getting 404 errors on sub domains with the Top Level Categories plugin, then I can highly recommend to switch to WP No Category Base.
Enjoy!
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