odd problem with vlc-3.0.4 (AlienBobs package)
 

Slackware 64-current multilib MATE desktop on Lenovo laptop.

After upgrading to the latest vlc version I've got the following problem:
when viewing a video in fullscreen mode, the control bar randomly ceases to appear when moving the cursor. Also, toggling fullscreen mode on/off with the "F" key won't work. Intermittently those functions reappear, to be gone again after a short time.
Toggling fullscreen by double-clicking works fine. I can also activate the floating control menu by right-clicking.

Same thing when trying a package built with Christoph Willing's SBo script. But a 3.0.3 package from that script works OK.

Reinstalling dependencies (libxkbcommon, qt5, qt5-webkit) makes no difference.

Hardly a hardware or driver issue since no other applications are affected. In order to eliminate a faulty touchpad I've tried connecting a mouse, but no difference.

I have an old Asus eee notebook with 32-current and xfce DE, and there vlc-3.0.4 works as it should.

A lot more applications installed on the Lenovo so it could be that some other package interfer, but since vlc functions after all I'm not tempted to uninstall/reinstall them one by one.

Any hints/suggestions greatly appreciated.

I would hint to consult the change-log, since it's only 3.0.3 to 3.0.4 - it might be right there ?