Is there a guide for this somewhere? I could look myself but if there is a suggested way to do it then it’ll save me a bit of time :p
@ Modemlooper, make a list? Don’t think the plugin developers are going to check all the css to see if they’re might be classes they could use.
Well its the usual things like buttons that have been styled in a plugin that should be pulling the BP css styles so it fits into the default css. There is going to be ton of BP child themes and most will use the default classes just restyled. This will make plugins fit better. Layout is ok in a plugins css but colors, fonts and links should match up to the default BP css.
My advice is to submit patches or talk to the authors of those plugins.