Carryover evaluation: Masking

[nairnandu]

To evaluate continuation of the Masking focus area in Interop 2024

Original proposal:

• Better Support for CSS masks #148

Labeled tests (2023):

• All tests
• Failing tests

Also consider the possibility of adding new tests in 2024

[jsnkuhn]

As the person that specifically asked about better support for mask-image I must say I'm concerned to still see Chromes 18% support. I know that there are still 3 months left in the year but to see pretty much no progress on this at all 9 months into the year is honestly disheartening.

[foolip]

@jsnkuhn the Chrome team is working on the Masking focus area and we expect to make good progress in the last 3 months of the year.

[thebabydino]

Chromium browsers have a non-standard text value for mask-clip - any chance this could become standard? It could be so useful.

One use case is for glassmorphism effects on text. This effect could also be achieved in Firefox using element(), but it requires an extra element.

Another use case is for getting such alpha XOR :hover/ :focus animated gradient ghost buttons.

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Another missing feature of masking would be the ability to subtract a mask layer from the result of compositing the layers below it - we can currently only perform the subtraction the other way around. Though I guess cross-browser support for luminance masks could help there.