Maybe a newer regression than what the original issue is about, but I can confirm that for me the unocss.root option has stopped working as of extension version v66.6.4. I traced this manually by shifting the version until I observed the issue.

If I revert the extension to v66.6.2, things start working as expected again. 🤔

Not sure if it is relevant info, but I use the latest version of VSCode on macOS, and am using a .code-workspace file to define the unocss root in a multi root workspace.

Originally posted by @danielwaltz in #3739