1252872 - Ellipsis doesnt respect z-order

Status: RESOLVED DUPLICATE of bug 886716

(Core :: Layout, defect)

Description

[bdesef]

Attachment: EllipsisStacking

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:44.0) Gecko/20100101 Firefox/44.0
Build ID: 20160210153822

Steps to reproduce:

Assume you have an element overlapping another one, not by z-order or DOM order but by that fact that it is CSS positioned. The element below is still position: static and contains too much text, indicated by text-overflow: ellipsis.


Actual results:

While the element below and its text are hidden behind the upper one correctly, only the ellipsis is at the very foreground (see attachment).


Expected results:

Ellipsis and text should behave in the same way. This change must have been introduced in one of the last versions, it was never an issue before.

Comment 1

[Loic]

Could you attach a screenshot of the current rendering and the 'good' past rendering, please?

Comment 2

[Loic]

Ok, no need.

Comment 3

[Daniel Holbert [:dholbert]]

(In reply to bdesef from comment #0)
> This change must have been
> introduced in one of the last versions, it was never an issue before.

I don't think this is actually true -- I can reproduce this bug in Firefox 15 (released back in 2012).  The ellipsis shows up on top of the overlay in the attached testcase, just like it does in recent builds.

(Haven't tested builds older than that.)

Do you have a specific URL where this happens, which you believe to have only started triggering this bug recently? It's possible there's something else related that *did* break recently, which your full site triggers but the testcase does not.

Comment 4

[Daniel Holbert [:dholbert]]

I believe this is actually the same issue as bug 886716. (The testcase here is essentially a simpler version of the testcase that's linked over there.)

I'm going to mark this as a duplicate, and improve the summary of that other bug to make it more discoverable. (Hopefully we can fix it before too long, too.)

Comment 5

[bdesef]

(In reply to Daniel Holbert [:dholbert] (mostly AFK March 3rd - 6th) from comment #3)
> Do you have a specific URL where this happens, which you believe to have
> only started triggering this bug recently? It's possible there's something
> else related that *did* break recently, which your full site triggers but
> the testcase does not.

I noticed the behavior here: http://illertal-gymnasium.eu/. The live@IGV box provides information on hovering one of the items. If you hover one of those on the left side, the dots from the right side overlap. But now that I've filed this bug report I noticed that I can easily fix the problem simply by giving the overlaying <div> a z-index, so the problem is circumvented on this site now. Perhaps I didn't check the design for some time, but when I built this site, the error was definitely not there.