[Bug] Themes are unable to import local files to their stylesheet

[intrnl]

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Describe the bug

Title explains it all, themes are unable to import local files on the theme's directory with relative path.

To Reproduce

theme/
  background.jpg
  config.json
  index.scss

// index.scss
body {
  background-image: url('./background.jpg');
}

Expected behavior

The relative path should be transformed into the base64'd version of the file that was pointed at.

body {
  background-image: url(data:image/png;base64,d2h5IGRpZCB5b3UgZXZlbiBib3RoZXIgZGVjb2RpbmcgdGhpcywgaXQncyBwb2ludGxlc3MsIHN0b3AgaXQu);
}

Screenshots

No screenshots necessary

System information

Manjaro Linux 5.0.2, Discord Stable

Additional context

plsfix

Are you willing and able to fix this?

Perhaps.