::before pseudo-element + procedural filters like :has-text() doesn't work

[MasterKia]

Prerequisites

• I verified that this is not a filter list issue. Report any issues with filter lists or broken website functionality in the uAssets issue tracker.
• This is not a support issue or a question. For support, questions, or help, visit /r/uBlockOrigin.
• I performed a cursory search of the issue tracker to avoid opening a duplicate issue.
• The issue is not present after disabling uBO in the browser.
• I checked the documentation to understand that the issue I am reporting is not normal behavior.

I tried to reproduce the issue when...

• uBO is the only extension.
• uBO uses default lists and settings.
• using a new, unmodified browser profile.

Description

This filter only works on Chromium (v115) and doesn't work on Firefox (v116):

www.bing.com##li.b_algo:has(div) h2::before:style(content: 'Second Text' !important; color: #E6000D !important;)

But this one without :has() works in both browsers:

www.bing.com##li.b_algo h2::before:style(content: 'First Text' !important; color: #E6000D !important;)

A specific URL where the issue occurs.

https://www.bing.com/search?go=Search&q=download+vlc&qs=ds&form=QBRE

Steps to Reproduce

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Expected behavior

.

Actual behavior

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uBO version

1.51.1rc1 dev

Browser name and version

.

Operating System and version

.

[gwarser]

Native has not enabled in Firefox yet?

[gorhill]

It's not possible to programmatically query a selector using ::before, so it's not something that can be fixed. Your selector li.b_algo:has(div) h2::before requires a procedural filter for platforms not supporting native :has(), thus that filter can't work.

uBO should report such filter as en error in Firefox, so that is the thing to fix.

[MasterKia]

Native has not enabled in Firefox yet?

No: https://caniuse.com/css-has

uBO should report such filter as an error in Firefox, so that is the thing to fix.

Also :has-text() doesn't work with ::before on both Chromium and Firefox.

www.bing.com##li.b_algo:has-text(a) h2::before:style(content: 'Second Text' !important; color: #E6000D !important;)

[krystian3w]

May post was not spam... screen shows a CSS4.

[JobcenterTycoon]

Native has will be enabled by default in Firefox 121 https://caniuse.com/?search=%3Ahas()

[u-RraaLL]

Native has will be enabled by default in Firefox 121 https://caniuse.com/?search=%3Ahas()

But:

Pseudo-elements are also not valid selectors within :has() and pseudo-elements are not valid anchors for :has().

https://developer.mozilla.org/en-US/docs/Web/CSS/:has

Edit: Which I now read is not the issue here... Anyway, 9 more days to the release.