Under Wayland when I tried searching in the widget explorer, the search field did not receive keyboard focus and my typing went into the Konsole from which I had started Plasmashell. Reproducible: Didn't try
I can confirm this. I am running plasma-wayland-devedition-gitunstable-20170128-2117-amd64.iso
Can confirm too, Plasma v5.9.2
Keyboard input in search field works on plasma 5.10 beta running under Wayland.
*** This bug has been marked as a duplicate of bug 369867 ***