There seems to be an issue with where a ColorDialog appears when using multiple monitors of the same model. From my observations, when a color dialog is opened, each monitor is assigned a name based on the model of the monitor being used. However if the monitors are the same model they will be assigned the same name. This therefor causes an issue resulting in a the ColorDialog being opened on the wrong monitor.
Attached is a simple project which can be used to replicate the problem, as well as a brief video displaying how to replicate the issue and what it looks like.
It is important to note, that when using monitors of different models, this issue will not occur.