Targus USB-C Dual 4k - visual glitch
 

Dock: Targus USB-C Dual 4k
Monitor: Dell u2718q
Computer: i7 Mac mini
Cable: HDMI, unknown brand

I'm experiencing some visual glitches related to certain apps (just Sublime Text so far). They appear or disappear when I move the window (shown in white) around, but stay in the same places when they're visible. I've seen this horizontal line of random green pixels appear at two different vertical locations on the screen. The green will turn purple depending on whether my Sublime Text window is behind it.

Has anyone seen anything like this? Any suggestions?

PS. Sorry for the blurry photo. I can't take a screenshot of the glitch.