[Tracking Requested - why for this release]: Looks like this is a regression. In old builds, the left part of the testcase is tall like the right part of the testcase (and like in Chrome). Regression range: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=fb2b08c6bc8c320127586fcedb2626e496bf3dcf&tochange=ee89deeb4fb6d12456c551c5ab4aaae151ceedae --> Probably regression from bug 1492538.
Bug 1725973 Comment 2 Edit History
Note: The actual edited comment in the bug view page will always show the original commenter’s name and original timestamp.
Looks like this is a regression. In old builds, the left part of the testcase is tall like the right part of the testcase (and like in Chrome). Regression range: https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=fb2b08c6bc8c320127586fcedb2626e496bf3dcf&tochange=ee89deeb4fb6d12456c551c5ab4aaae151ceedae --> Probably regression from bug 1492538.