Bug in Lyx 1.3.4 ?

[Pavel Sanda]

On Wed, Feb 05, 2020 at 08:32:21AM +0100, emile lunardon wrote:
> When I try to enter, under LyX 1.3.4 (Linux), one of the two Math symbols
> shown in the attached file (written with LyX 1.3.3), there is a crash of
> LyX 1.3.4 with the attached messages.
> 
> Can someone confirm this strange phenomena ?

I can not (tried with Qt 4 as you do). (My entering was copy paste from your document.)
Your backtrace is not much useful, if you compile on your own we would need it with debug symbols...
Pavel