1387931 - Don't generate pseudo elements for ::before and ::after if content property is 'none' or 'normal'

Status: RESOLVED WONTFIX

(Core :: CSS Parsing and Computation, defect, P3)

Description

[Hiroyuki Ikezoe (:hiro)]

From the spec [1];

 none
     The pseudo-element is not generated.

Stylo does not pseudo elements at all.

[1] https://www.w3.org/TR/CSS21/generate.html#content

Comment 1

[Hiroyuki Ikezoe (:hiro)]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=539ae2c3258394e9c6aa7f73a30dfb5a763ba22a
I have no idea how to test this without checking whether animation was created on the pseudo element which has 'content:none'.

Comment 2

[Chris Peterson [:cpeterson]]

Hiro, is this a bug we need to fix in Stylo? Or a bug in Gecko's style system?

Comment 3

[Hiroyuki Ikezoe (:hiro)]

Tight, this is a gecko bug, stylo handles the case correctly.

Comment 4

[Chris Mills [:cmills]]

Marking as part of documentation plan for intentional stylo differences, just in case this is fixed before stylo hits release.

Comment 5

[Chris Mills [:cmills]]

Documented:

https://developer.mozilla.org/en-US/docs/Web/CSS/::before#Quantum_CSS_notes
https://developer.mozilla.org/en-US/docs/Web/CSS/::after#Quantum_CSS_notes
https://developer.mozilla.org/en-US/docs/Web/CSS/content#Quantum_CSS_notes
https://developer.mozilla.org/en-US/Firefox/Releases/57#Quantum_CSS_notes

Comment 6

[Hiroyuki Ikezoe (:hiro)]

Closing since this is a bug for the old style system.