Qt applications running on s390x (or ppc64 or any other big endian platform) print this warning:

qt.qpa.input: failed to select events, window 2600006, error code 2

and the mouse wheel does nothing.

Apparently this is a known issue as various distributions apply patches like https://github.com/jnielen/void-packages/blob/dc1291b3d104839a6eb2111ba2c4a0128673a551/srcpkgs/qt5/patches/0049-big-endian-scroll.patch, but I could not find a report here.