Board Thread:Support Requests - Designing Your Wiki/@comment-1807002-20190722221733/@comment-9605025-20190722233909

You need to import it on one of your main site CSS pages. You can read about how to do that here. Although the method with load.php is more efficient when it comes to loading, it essentially hides which style sheet the CSS is on; that is why you had trouble finding it. The alternative loads one at a time so is less efficient. However, as noted, each style sheet is individually identified. This is true in Internet Explorer and Chrome as well, not just Firefox (which is the only one mentioned on the help page).