Comment # 20 on bug 1120397 from Takashi Iwai

Sorry, I don't know, it's better asked to lxqt-sudo package maintainer or
project maintainer.  But I won't be surprised if it would have worked with the
older version casually.  The command string quotation seems to have been
changed in the recent version, judging from the source code.

In anyways, AFAIK, lxqt-sudo always takes the multiple arguments, hence I guess
it'd be OK to apply the workaround to Leap 15.1 as well.  But one needs
verification.  (Don't ask me, I've been never LXQt user :)