1605473 - 'content: none' behaves like 'content: normal' in ::marker instead of destroying it

Status: RESOLVED FIXED

(Core :: Layout: Generated Content, Lists, and Counters, defect, P3)

Description

[Oriol Brufau [:Oriol]]

From https://drafts.csswg.org/css-lists/#content-property,

• content on the ::marker itself is not normal
  The contents of the marker box are determined as defined by the content property, exactly as for ::before.

From https://drafts.csswg.org/css-content-3/#valdef-content-none

On pseudo-elements it inhibits the creation of the pseudo-element as if it had display: none.

Well, display doesn't apply to ::marker, but the first part of the sentence seems clear that no marker box should be generated.

However, in Firefox it behaves just like content: normal.

In Chromium I have the same problem since both normal and none are stored as nullptr.

Comment 1

[Emilio Cobos Álvarez (:emilio)]

Yeah, we have the exact same issue, basically, which was long-standing since before our style system rewrite:

document.body.style.content = "normal"
"normal"
getComputedStyle(document.body).content
"none"

Because both are stored as an empty array.

Here is where this distinction is lost.

Comment 2

[Emilio Cobos Álvarez (:emilio)]

The refactoring in bug 1605803 will allow to fix this trivially.

Comment 3

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

MDN probably needs to be updated for content:none / content:normal on ::marker when this is fixed, too.
devdoc-needed?

Comment 4

[Oriol Brufau [:Oriol]]

BTW, I added some WPT tests about this:

• css/css-pseudo/marker-computed-content.html
• css/css-pseudo/marker-computed-size.html
• css/css-pseudo/marker-content-019.html

Comment 5

[Emilio Cobos Álvarez (:emilio)]

Thanks Oriol!

Comment 6

[Emilio Cobos Álvarez (:emilio)]

(And sorry, I'm a bit swamped with other things atm)

Comment 7

[Oriol Brufau [:Oriol]]

Since this has not been fixed, I would assume content:none behaves exactly as content:normal
But then why is this test failing in Firefox? https://wpt.fyi/results/css/css-pseudo/marker-content-020.html
It seems some pixels are different (though I can't detect it if I disable highlight diff)
https://wpt.fyi/analyzer?screenshot=sha1%3A88511f75bca2f25537d7d5d1bb8d4ac6686bdb2c&screenshot=sha1%3Aabfd224f3e20313ee8a6c04c0e45abbc0bf89d0e

Comment 9

[Oriol Brufau [:Oriol]]

Assigning to Mats per bug 1699949

Comment 10

[Mats Palmgren (inactive)]

Attachment: Bug 1605473 - Implement 'content: none' for ::marker. r=emilio

Comment 11

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

There's a r+ patch which didn't land and no activity in this bug for 2 weeks.
:mats, could you have a look please?
For more information, please visit auto_nag documentation.

Comment 12

[Mats Palmgren (inactive)]

Intent to ship: https://groups.google.com/a/mozilla.org/g/dev-platform/c/CJ6ZRmOMkao

Comment 13

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/0044af746b47
Implement 'content: none' for ::marker.  r=emilio

Comment 14

[Marian-Vasile Laza]

https://hg.mozilla.org/mozilla-central/rev/0044af746b47