XF 2.2 How to use Bootstrap without creating an add-on

You'll need to include the bootstrap JS and CSS on pages where you're trying to use it


You can do this by loading it from the CDN sources, or you can host it locally on your server.
 
Just because you can, doesn't mean you should.

Seriously, bootstrap is super heavy. and if all it's for is a widget, don't add that kind of page weight to style a few blocks.
 
It is quite easy to have a look at the CSS and create some classes that basically do the same, as long as it is about the more simple, merely visual stuff, not sth. that requires jQuery libs. Stuff like buttons, forms etc.
 
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