I encounter a problem that is a little aggravating in the long run, When I launch SolidWorks, on the task pane tab ColorChart runs automatically and is displayed in the foreground The option is unchecked in Customization.
Have you looked in your supplements? For my part, I deactivated it as soon as it arrived as well and it never came back but I think I simply unchecked it from the customization as you did.
At first to stop it from being displayed first you can move it to your customization pane, when you hover the smile over it dots appear on the right that allow you to move it up for example, as this solid will not display it in the first place