mask-border CSS shorthand

[stubbornella]

Description

The mask-border CSS property sets how the edges of an element are masked. It is a shorthand for mask-border-outset, mask-border-repeat, mask-border-slice, mask-border-source, and mask-border-width.

Specification

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

Additional Signals

No response

[gsnedders]

https://wpt.fyi/results/css/css-masking?label=master&label=experimental&aligned&q=mask-border doesn't match much; we probably need to split through variants the following to have mask-border tests specifically:

css/css-masking/inheritance.sub.html
css/css-masking/mask-shorthand-subproperties-reset.html
css/css-masking/parsing/mask-valid.sub.html

[nt1m]

https://github.com/search?q=repo%3Awebkit%2Fwebkit+mask-box-image&type=code&p=1

This is just a renamed version of -webkit-mask-box-image, those LayoutTests could just be ported over to WPT if rendering tests are needed.

[wpt-interop]

Thank you for proposing mask-border CSS shorthand for inclusion in Interop 2025.

We wanted to let you know that this proposal was not selected to be part of Interop this year.

On behalf of the entire Interop team, thank you for submitting this proposal for consideration. We got many more proposals than we could include in this year's project, necessitating some difficult choices. Please note this should not be taken as a comment on the technology as a whole, or our willingness to consider it for Interop in the future. We appreciate the work you put into your proposal, and would welcome your participation in future rounds of Interop.

For an overview of our process, see proposal selection. Thank you again for contributing to Interop 2025.

Posted on behalf of the Interop team.