When dragging a TAdvToolPanel, it is very slow and also slowly draws an outline of the panel and does not erase the previous position's outline. Dragging around and around and you have this mess of rectangles until you release the mouse button. Sometimes, maybe half the time, it leaves some pieces of several of previously drawn rectangles.
I also set the ShowClose button to false, and as long as it is docked, the close button is not shown, however once dragged to a new position it re-appears, allowing the panel to be closed.
Delphi 10.2
TAdvToolBar 1.6.0.2
Dell Inspiron i7-7500U, 2.70GHz, 12GB RAM
Windows 10, 1709
Intel HD Graphics 620, driver 22.20.16.4836, 2017-10-17
We see some slowness but cannot see that it does not erase previous positions.
The handling of this is unfortunately at the level of the VCL base class TPanel that is set in floating mode. Unfortunately, little of this TPanel behavior can be modified in a descending class, so we would need to look to replace the base class, but this isn't a trivial exercise and will cost time.
Same thing occurs on my desktop, Nvidia GeForce GT730, so doubtful it is a video driver issue. I can post a video of it if you'd like. Really easy to get it to leave ghosts of the border drawing as you drag it around off of the AdvToolPanelTab during run time and which most remain after stopping the dragging.
But not that important as I found an alternative docking control that appears to better fit my needs.