1470025 - User Agent stylesheet default opacity for placeholder text

Status: NEW

(Core :: Layout: Form Controls, enhancement)

Description

[Karl Dubost💡 :karlcow]

This will be used to track the webcompat issues related to the differences of default opacity in between Gecko and WebKit/Blink.

Firefox:      0.54
WebKit/Blink: 1


* The CSS WG agreed that User Agent Stylesheets should be tested.
  https://github.com/w3c/web-platform-tests/issues/5625
* Someone at Google thinks it would be good to define what it should for interop
  https://github.com/whatwg/html/issues/2561#issuecomment-296130295

Comment 1

[Mike Taylor [:miketaylr]]

Would be good to fix this issue interop for GeckoView.

Comment 3

[Firefox Bug Husbandry Bot]

See bug 1547409. Migrating webcompat priority whiteboard tags to project flags.

Comment 4

[Thomas Wisniewski [:twisniewski]]

There does not seem to have been any progress on this despite the WG agreeing that it should be done. As such we still need web platform tests here.

Comment 5

[Karl Dubost💡 :karlcow]

Attachment: GitHub Pull Request

Comment 6

[Bill Goldstein [:aja] (UTC-6)]

In Gecko:
Perhaps use ::placeholder { opacity: 1.0; color: color-mix(in srgb, currentColor 54%, transparent); }
or use ::placeholder { opacity: 1.0; color: rgb(from currentColor, r g b / 54%); }
once css-color-5 Relative RGB colors are supported.
And possibly alias ::-webkit-input-placeholder to ::placeholder

In Blink:
Create dark color-scheme
::-webkit-input-placeholder { color: -internal-light-dark() }
and use that until one of the two methods above.

Comment 7

[BugBot [:suhaib / :marco/ :calixte]]

The bug assignee is inactive on Bugzilla, so the assignee is being reset.

Comment 8

[Suhaib Mujahid [:suhaib]]

Sorry, there was a problem with the detection of inactive users. I'm reverting the change.

Comment 9

[Thomas Wisniewski [:twisniewski]]

Actually, Karl isn't with Mozilla anymore, so we might we as well unassign the bug for now.

Comment 12

[Emilio Cobos Álvarez (:emilio)]

Doing something like the color-mix in comment 6 seems reasonable to me, fwiw.

Comment 13

[Thomas Wisniewski [:twisniewski]]

Moving the still-reproducible webcompat links to bugs dependent on our knowledge base bug for this issue, bug 1847183.