1600536 - user-select: initial/auto on input works incorrectly

Status: VERIFIED FIXED

(Core :: DOM: Selection, defect)

Description

[abc]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:70.0) Gecko/20100101 Firefox/70.0

Steps to reproduce:

1. open https://www.bilibili.com/video/av77577858?spm_id_from=333.851.b_7265706f7274466972737431.7 on firefox 70.x
2. login your account
3. input some text in danmaku sendbar
4. select some text via mouse or touchpad

Actual results:

text cannot be selected or selected text incorrectly

Expected results:

selected text correctly as mouse or touchpad selected.

more details:
It works fine on Safari, Chrome, Edge.
It seems that issue was caused by parent user-select value.

reproduce video:
https://www.youtube.com/watch?v=lmrp4lt_9gg

Comment 1

[Edgar Chen [:edgar]]

I could reproduce this issue, I am still trying to find a minimum test script.

Comment 2

[Edgar Chen [:edgar]]

Here is the minimum script: https://software.hixie.ch/utilities/js/live-dom-viewer/?saved=7528

Per spec, https://drafts.csswg.org/css-ui-4/#valdef-user-select-auto

• The computed value of auto is determined as follows:
  • On the ::before and ::after pseudo elements, the computed value is none
  • If the element is an editable element, the computed value is contain
  • Otherwise, if the computed value of user-select on the parent of this element is all, the computed value is all
  • Otherwise, if the computed value of user-select on the parent of this element is none, the computed value is none
  • Otherwise, the computed value is text

The computed value of user-select for <input> and <textarea> should be contain which allows selections allow selections to extend across this element. We don't support contain at this moment, I think this is why it doesn't work.

Comment 3

[Emilio Cobos Álvarez (:emilio)]

This is not why it doesn't work. Instead of contain we have independent selection for <input> and such.

Is this a regression?

Comment 4

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1600536 - user-select: auto on input / textarea should behave as text. r=mats

This is covered by existing tests, via the removal of the rule in forms.css

Comment 5

[Alice0775 White]

Regression window:
https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=31edd1840c5f651b5dbf182fdb7f04fe98c88d86&tochange=9fbf850dc78d7197132a298f9ec0270c7de16a13

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/964b6feba6a4
user-select: auto on input / textarea should behave as text. r=mats

Comment 7

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/964b6feba6a4

Comment 8

[Emilio Cobos Álvarez (:emilio)]

Not really a regression. Before that you could repro the bug with -moz-user-select instead of the -webkit- variant.

Comment 9

[Cristian Fogel [:cfogel]]

Confirmed issue with a Nighly build from 2019-12-09.
Managed to verify the fix wit 73.0b11 on macOS 10.15