1378065 - Selected text with some Unicode characters can move up and down on pointer/mouse cursor movement

Status: VERIFIED WORKSFORME

(Core :: Layout: Form Controls, defect, P3)

Description

[Virtual_ManPL [:Virtual] 🇵🇱 - (please needinfo? me - so I will see your comment/reply/question/etc.)]

Attachment: screencast.mp4

[Tracking Requested - why for this release]: Regression

STR:
1. Paste this text
> 初音ミクがオリジナルを歌ってくれたよ「ブラック★ロックシューター」
into address bar, search bar, find bar, bookmark doorhanger/panelUI, Library, etc. and even on website pages, it happens on all 1 line areas where you can paste some test
2. Select some part of the pasted text
3. While keeping selection, move pointer/mouse cursor up and down few times
and see that text also going up and down

Comment 1

[Alice0775 White]

I can also reproduce the problem on Nightly56.0a1 Windows10.

Comment 2

[Alice0775 White]

Regression window:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=5533bb0145694e5d8574909e4de66847ab84be8c&tochange=b7a6ec5eb1e1ff88d9ebc278de9ea3cd761f763f

Regressed by: b7a6ec5eb1e1	Masayuki Nakano — Bug 548311 Change Japanese default fonts only on early Beta and Nightly r=emk,jfkthame,m_kato

Comment 3

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

Looks like it's line-height issue of <input> element because Meiryo's default line-height is higher than other fonts'.

If we'd increase height of <input> element, it could cause breaking some websites' layout. Also, we could use |overflow-y: hidden;| for the anonymous <div> in <input> element but even if we could do that, it's really risky for other languages. E.g., I worry about Devanagari (IIRC, some South-Asian characters require higher space than usual).

Other possible scenario is, we hack metrics of Meiryo. As far as I know, the computation of normal line-height is different from Blink. Our line-height is higher than them and it causes unexpected overflow. (Although I saw it only in a website and I reported that to the company directly.)

Fortunately, underscore is not hidden by this bug. So, not so important issue. Although I don't like this kind of bug.

Comment 4

[Xidorn Quan [:xidorn] UTC+10]

FWIW, it seems to me that Meiryo is constantly 1px shorter in Blink than in Gecko regardless of font-size.

Comment 5

[Julien Cristau [:jcristau]]

Marking 55 disabled, as this font is only used in nightly and early beta (the next beta build this week will have that unset)

Comment 6

[Liz Henry (:lizzard) (relman/hg->git project)]

Looks like Masayuki is aware of the regression and considers it minor. 
So I don't think release management needs to track this bug. It would be nice to fix it since we have STR, though.

Comment 8

[Liz Henry (:lizzard) (relman/hg->git project)]

Long standing regression,

Comment 9

[Liz Henry (:lizzard) (relman/hg->git project)]

I meant to say, we should stop triaging this and leave it to the component owner.

Comment 10

[Neha Kochar [:neha]]

Bulk change for all regression bugs with status-firefox67 as 'fix-optional' to be marked 'affected' for status-firefox68.

Comment 11

[Tim Spurway [:tspurway]]

[bulk change 69 status -> --- b/c to stop re-triaging old regressions every release]

Triage Owners: please do not set release status tracking flags in new releases unless this bug will actually be worked on

Comment 12

[Hani Yacoub, Desktop QA]

I couldn't manage to reproduce this issue. Closing this bug as resolved: Worksforme.

Comment 13

[Virtual_ManPL [:Virtual] 🇵🇱 - (please needinfo? me - so I will see your comment/reply/question/etc.)]

The issue does not occur anymore on Mozilla Firefox 96.0a1 (2021-11-04), so I am closing this issue as WORKSFORME.