I have same problem on same configuration X1 G9 ThinkPad Thunderbolt 3 dock Gen2 / Workstation dock. But i am using both HDMI ports not Display ports. Any idea if i can do anything. i am sick of my screens to lose connection suddenly for few sec and come back.
my maschine: X1 Yoga 1st Gen (Type 20FQ, 20FR) Laptop (ThinkPad) - Type 20FR Intel HD Graphics 520 I just bought an ultra wide monitor with a recommended resolution of 5120 x 1440.