Background: External monitor hooked up through HDMI to 14" Laptop. External Monitor is primary display. Distro: kubuntu 16.04 x64 (kde5)

So I can click on the Application Launcher (Start Menu) just fine on either monitor, it opens on that monitor.

However, if I have my Laptop Monitor on and I hit Alt+F1 to open the Application Launcher, it only shows up on my Laptop Monitor even though my External Monitor is the primary display. Alt+F1 works fine for my External Monitor if my laptop is closed or its display is disabled.

It's inconvenient because when my laptop is open, I only use its monitor sparingly. I don't want to have to go in to my display settings to constantly enable/disable it.

I'm not sure if this is a bug or if some setting is flipped somewhere. I couldn't find any other users experiencing it, but I can file a bug report if that is needed.