Subject: bug#27647: 26.0.50; Line numbers implemented natively disappear momentarily when frame out of focus

From: martin rudalics <[email-masked]>
Date: Tue, 17 Oct 2017 10:59:15 +0200

> I have yet to find a recipe from emacs -Q, but below is a GIF recording:
 >
 > ==> https://i.imgur.com/kB6gHDk.gifv <==

Apparently you move the mouse to some strange glyph on your mode line.
Which one is that?  Other mode lines elements do not seem to cause it.

martin