1496065 - Consider removing support for referencing arbitrary content using -moz-element()

Status: NEW

(Core :: Layout: Images, Video, and HTML Frames, task, P3)

Description

[Jonathan Watt [:jwatt]]

We shipped support for -moz-element() 8 years ago:

https://hacks.mozilla.org/2010/08/mozelement/
https://bugzilla.mozilla.org/show_bug.cgi?id=506826

The prefixless element() function is still in:

https://drafts.csswg.org/css-images-4/#element-notation

but after 8 years no other implementation has added support for this feature. We should perhaps consider removing at least the support for referencing arbitrary elements since the invalidation complexity that it adds is undesirable. Support for <canvas> and a few other elements seems non-problematic to me.

Comment 1

[Cameron McCormack (:heycam)]

That sounds fine to me.

Comment 2

[Cameron McCormack (:heycam)]

Although we should maybe gather some telemetry to check nobody's using it.

Comment 3

[Jeff Muizelaar [:jrmuizel]]

I would support removing it. I've been bitten by it's implementation complexity more than once.