As shown in the second item in the reading list from the screenshot attachment the title is long and wrapping but wraps to a 3rd line which causes it to partially display. This is a notorious CSS issue to which there are many hacks.

Also to note that the top of summary text should be aligned with top of preview image (currently text is a few pixels up too far on OS X) http://cl.ly/image/3z3W2J2Z3i36 Florian notes this might actually be the cause of having a few pixels of the 3rd line of text visible.

This sounds like Bug 1143689.

(In reply to Andrei Vaida, QA [:avaida] from comment #2) > This sounds like Bug 1143689. Let's fix the partially visible 3rd line here, and keep bug 1143689 for the missing ellipsis. (In reply to Bryan Clark (Firefox PM) [:clarkbw] from comment #1) > Also to note that the top of summary text should be aligned with top of > preview image (currently text is a few pixels up too far on OS X) > http://cl.ly/image/3z3W2J2Z3i36 > > Florian notes this might actually be the cause of having a few pixels of the > 3rd line of text visible. This turned out to not be related, I'm (mostly) fixing this misalignment with the CSS changes in bug 1123525.

There's currently a "2.8em" hardcoded height value. I suspect this value has been selected empirically to fit on Windows. To show correctly 2 lines of text, we need to have twice the line-height. Unfortunately I don't think there's any CSS-only way to get that size, so using a value relative to em is probably our best approximation. I looked at the (default) line height values and the font-size values on Windows 7, Ubuntu 13.10 and OS X 10.10. 'line height / font-size * 2' gives these values: Mac: 2.45 Ubuntu: 2.32 (can be rounded down to 2.3 without visible difference) Windows: 2.83 (can be rounded down to 2.8 without visible difference; I think that's where our current value comes from). This patch is making that height value platform specific, using 2.45em, 2.3em and 2.8em for Mac, Linux and Windows respectively. It's not a real fix, but I think it will hide the problem almost everywhere.

Comment on attachment 8579619 [details] [diff] [review] Patch Review of attachment 8579619 [details] [diff] [review]: ----------------------------------------------------------------- We handled something very similar to this for the Firefox menu, but we didn't need platform specific values there. Maybe we need to specify line-height? And you can use clip: rect(); to manually chose the clipping rectangle. https://dxr.mozilla.org/mozilla-central/source/browser/themes/shared/customizableui/panelUIOverlay.inc.css#201-202,212-213 for the Firefox menu panel CSS that does this there.

Fair enough, let's just set the line-height. I was reluctant to override the OS-specific system line height, but this has the advantage of also fixing the bug for non default system font sizes :).

Verified fixed on Nightly 39.0a1 (2015-03-23), using Ubuntu 14.04 (x64), Mac OS X 10.9.5 and Windows 7 (x64).

Verified fixed on Aurora 38.0a2 (2015-03-29) as well, using Windows 7 (x64), Ubuntu 14.04 (x64) and Mac OS X 10.9.5. Please note that this scenario is still affected by Bug 1143689, as there's still no ellipsis displayed for the item titles.