I have a 2015 macbook pro running Fedora 25, and attach an external 4k monitor over displayport. I frequently get temporary signal drop outs that only affect the external monitor. The dropouts only last a second or two however is quite annoying. I have this problem with 2 separate 4k monitors (one at work and one at home), of different models and using different cables.
Using Gnome 3.22.3
There is no output in either journal or dmesg when the problem occurs.
Any guidance on where to debug next would be nice. Not sure if this is a wayland issue or not.