User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:64.0) Gecko/20100101 Firefox/64.0

Steps to reproduce:

1. Create an element with position: sticky or position: fixed, but do not give it a z-index.
2. Create an element below the element created in step 1, and that has text-overflow: ellipsis and text that overflows the element, so that the text is truncated and ellipsis appear.

Actual results:

The ellipsis appear above the position:sticky or position:fixed element, but the text does not.

See this JSFiddle for an example: https://jsfiddle.net/p6v0zbqg/1/ - You can see the ellipsis overlapping the position:fixed and position: sticky elements. (you will have to scroll the container div for the position: sticky one).

Expected results:

The ellipsis should remain below the position: fixed and position: sticky elements, just like the text does.

Hi,

I've managed to reproduce this issue on Windows 10 and Ubuntu 16.04 using Firefox 64.0.2 and Firefox Nightly 66.0a1

I will add a component so that the developers can take a look at it.

Thank you for reporting!

Fixed in bug 886716 (Firefox 66).