1881220 - Text-overflow ellipsis incorrectly shown inside flex container, depending on length of text and font used

Status: REOPENED

(Core :: Layout: Flexbox, defect, P3)

Description

[@CSSence]

Attachment: Simplified Test Case

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:122.0) Gecko/20100101 Firefox/122.0

Steps to reproduce:

Go to https://codepen.io/cssence/pen/QWoPoBB or open attached file in Firefox (e.g. version 122) on any OS, preferably Windows or MacOS.

Actual results:

text-overflow: ellipsis is shown in certain cases (depending on length of text and font being used), despite there being no size contraint.

Expected results:

Same as in Chromium and Safari, no text-overflow: ellipsis should occur.

Comment 1

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

The Bugbug bot thinks this bug should belong to the 'Core::Layout: Flexbox' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Alice0775 White]

Regression window:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=5a3635bcdc01fb3d4b1d6e1d7410110c54a0fc2b&tochange=422af19ca706a86ef5b9a2ad0fa46e701b8a137d

Comment 3

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

:emilio, since you are the author of the regressor, bug 1841612, could you take a look? Also, could you set the severity field?

For more information, please visit BugBot documentation.

Comment 4

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1881220 - Change calc() resolution mode to always round than truncate-by-default. r=#style

The regressing bug regressed some calc() expressions like the one in the
test-case:

max-width: calc(100% - <some-fixed-length>);

Where floating point precision basically made us lose a little bit of
precision here and there.

Before bug 1841612, this worked because we'd operate in fixed point for
such simple expressions at least. Things could easily go equally south
for more complex things including e.g. rem().

Rounding seems like the better default for calc() since we basically
have no idea of what the output is going to be, and makes the answer
more likely to be precise.

Note that this only affects actual mixed calc() expressions: If things
resolve to a percentage we keep existing behavior.

Comment 5

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

Set release status flags based on info from the regressing bug 1841612

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/09a1b473f8da
Change calc() resolution mode to always round than truncate-by-default. r=firefox-style-system-reviewers,boris

Comment 7

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Created web-platform-tests PR https://github.com/web-platform-tests/wpt/pull/44811 for changes under testing/web-platform/tests

Comment 8

[Bob Hood [:bhood]]

Emilio, could you please apply Priority/Severity ratings here? It'll help release management.

Comment 9

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/09a1b473f8da

Comment 10

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Upstream PR merged by moz-wptsync-bot

Comment 11

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

The patch landed in nightly and beta is affected.
:emilio, is this bug important enough to require an uplift?

• If yes, please nominate the patch for beta approval.
• If no, please set status-firefox124 to wontfix.

For more information, please visit BugBot documentation.

Comment 12

[Emilio Cobos Álvarez (:emilio)]

This is not a particularly risk-free patch.

Comment 13

[Emilio Cobos Álvarez (:emilio)]

Reopening because we're reverting the fix in bug 1893127.