display of $int...$ under QT5

[Pavel Sanda]

On Wed, Aug 26, 2020 at 10:35:14PM +0200, M.B. Schiekel wrote:
> well, I use the openSUSE Leap-15.2 out of the box with
> TeXlive 2017.20170520-lp152.15.2 from Di 09 Jun 2020 07:46:23 CEST.
> esint10 is: texlive-esint-type1 - Font esint10 in Type 1 format.

This could be the problem. LyX ships its own version of esint10.ttf
and what you write above looks like TeXLive version.

Can you post all esint10.ttf found on your disk? Something like:
locate esint10.ttf
or
find / -name esint10.ttf 2>/dev/null

Pavel