CSS Design File features work when loaded directly but not via CSS File Folders

[davidjb]

CSS like:

#ees_toolBarLogo {
  background-image: url("./?a=12345:dist/images/logo.svg?v=%globals_asset_version:12345%");
}

resolves fine when the CSS Design File is loaded directly via its URL, but not when it is included as part of a CSS File Folder. Full list of aspects that don't resolve - and are sent to the client in the raw form - with this style of use:

• Asset URLs
• Keywords
• Matrix CSS comments
• SSJS

For note, all of the above work if the CSS Design File is loaded via its URL so the workaround is to avoid use of CSS File Folders. mysource_file/* links resolve in CSS File Folders, so that already works in both.

Also, conditional keywords always appear to never work -- they always appear to resolve as false in CSS Design Files (eg the conditional keyword block is stripped entirely, ignoring its content). That's less of an issue if SSJS is available and works in both areas.

[davidjb]

Reported at https://squizmap.squiz.net/matrix/10589