I’ve built kdenlive successfully in an artisinal, bespoke lxc container running Ubuntu 18.04 and with the KDE Neon user/lts repo added to get all that lovely KDE and Qt freshness.
The snapcraft.yaml looks like http://paste.ubuntu.com/p/BG6fJhYrz5/
This successfully builds a snap based on base:
core18 (which I appreciate is unstable).
I can install and run the snap in devmode on my 18.04 laptop, but when installed as a strict snap I get this with
= Seccomp = Time: Aug 29 18:27:14 Log: auid=1000 uid=1000 gid=1000 ses=4 pid=25457 comm="kdenlive" exe="/snap/kdenlive-devel/x2/usr/bin/kdenlive" sig=0 arch=c000003e 332(UNKNOWN) compat=0 ip=0x7fb389b00839 code=0x50000 Syscall: UNKNOWN
Here’s the full strace in case it’s useful. http://paste.ubuntu.com/p/9gjt2GDmQW/