On @container queries

[phaistonian]

It seems they are stripped from the extracted CSS.

Update

[michtio]

This is related to: nystudio107/rollup-plugin-critical#21
And: https://github.com/pocketjoso/penthouse/blob/8ebc6533606481de6669b38fe332b731882f1203/src/postformatting/final-rule-remover.js#L14-L46

penthouse is used under the hood (and seems unmaintained) - it doesn't support modern CSS @ rules.

[bezoerb]

There's a draft PR available which should fix that: #617