var(--tw-empty,/*!*/ /*!*/) wrongly processed

[TutorialDoctor]

TailwindCSS uses this workaround to set the value of a CSS variable to a single empty space:

--tw-ring-inset: var(--tw-empty,/!/ /!/);

This is valid but the sass compressor gives me the following when running tests:

Invalid CSS after "...pty,/*!*/ /*!*/": expected function argument, was ");"

There are more details around this in the following ticket:

tailwindlabs/tailwindcss#2889
tailwindlabs/tailwindcss#3328