[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

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

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

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.

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

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

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.

Long standing regression,

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