After upgrade / starting smplayer I have noticed this warning:
[andrzejl@wishmasus ~]$ smplayer
“Qt Warning – invalid keysym: dead_actute”
This is SMPlayer v. 14.3.0 running on Linux
After a bit of investigation I have found this.
a) open this file as root: /usr/share/X11/locale/en_US.UTF-8/Compose
b) search thorough it for the phrase:
c) replace the phrase with:
d) save the file.
There. Fixed. Enjoy.