MyBB Community Forums

Earlier i was on default mybb theme but now i am on cleanBB theme. Bit after shifting to this new theme sub forums under main forums are not appearing in 2 columns as earlier but instead are appearing like a paragraph. I tried changing number of columns from settings to 3 etc but this is not helping. Can anyone help me with this?

if you are using a plugin (eg.) for showing the subforums in columns then deactivate it and reactivate it.

most of the plugins do not work on newly installed themes unless we deactivate and reactivate them