Enable layout.css.properties-and-values.enabled

[yezhizhen]

Servo Companion: servo/servo#42136

Note that registered properties don't animate correctly: #38

[Loirooriol]

This doesn't address servo/servo#41417 (comment)

[yezhizhen]

This doesn't address servo/servo#41417 (comment)

But can't we leave it as a follow up? It is set as non-animatable in the fixup commits anyway, so shouldn't cause crash.

[yezhizhen]

But can't we leave it as a follow up? It is set as non-animatable in the fixup commits anyway, so shouldn't cause crash.

https://github.com/servo/servo/actions/runs/21329329850

There is no crash thanks to the fixup you proposed. So it is good for now?

[Loirooriol]

As a rule of thumb , features shouldn't be enabled until they are properly implemented, because otherwise it defeats feature checking and it can end up breaking more than it fixes.

But we don't supports @supports at-rule(), so maybe it's fine.

Still, thinking long-term I would like to do these king of things with experimental flags, which I don't think is currently possible for Stylo static prefs.