MATE Dock Applet: can't click with Touchscreen, only with touchpad or mouse

Hello,
I have Ubuntu MATE 16.04 running on a small laptop with a touchscreen (Asus E205SA).
I have it set up with Mutiny layout. The touchscreen is working fine, and I can click and double-click everywhere except on the MATE Dock applet on the left-side panel. When I touch there, the cursor follows my finger and is over the dock applet, but I can’t start any application.
I can click on the Menu button, on icons on the desktop, and the click registers and applications start as expected.
I can click on the Dock applet with mouse or touchpad and it works also as expected. It’s only with the touchscreen that it doesn’t react.
Has anyone experienced this? I don’t even know how to begin to troubleshoot this.