If you try to mix and match these two methods in your layouts:
i.e.
<link rel="stylesheet" type="text/css" href="css/blablah.css"/>
and
{{response.files.append(URL('static','css/blahblah.css'))}}I found out that some of my files i.e. CSS in this case where not being imported and applied to the layout. Till I choose a uniform method to import files to my layout. This behavior is somewhat strange and gave me a lot of troubles before figuring it out. Pystar
