Dave, sorry but you are wrong here. Microsoft designed the tray system many many years ago. (I believe even before the first version of SketchUp.) They work the same in all MFC applications. They were designed to be totally flexible. Ie, this means that the user has total control. The user can have as many tabbed docked trays as they wish. They can have others autohide (slide out) into whichever margin they wish. They can have whatever panels they don’t need hidden. They can have whatever panels they want in whichever trays they want. They can have some closed, some open, some docked, some floating, some auto-hidden, etc.
The SketchUp team only migrated the tool window inspectors over to tray panels. They didn’t “design” much (if anything) else about them.
Although it looked to me as if he had 2 panels per tray, many users that want a certain panel “on demand” via a keyboard accelerator, have these single inspector panels on a tray of their own, because it is the trays that can have shortcuts assigned to them.
When they use these shortcuts, the floating tray with it’s proper panel is displayed floating, used and then dismissed.
Some users with multiple monitors prefer these “on demand” trays to appear on the secondary display.
Incorrect. Review the video.
He has both the “Layers” and “Scenes” panels, within a custom tray named “Layer”.
Further more all his trays are docked and tabbed. He does not have them floating, he is complaining of a bug the keeps causing his “Layer” tray to undock and become attached to the mouse cursor when he adds a new scene to the model.
I myself, also use this dual panel per tray scenario, and have had no problems.
Back to the issue. I just tested a bit on SketchUp 2016, and I find that the issue happens intermittently, when one of the trays “thinks” that the tray tab was double-clicked. Simply, double-clicking again will redock the tray that is attached to the cursor, back where it was before.
I think it may be just that the timing of clicks needs to be lengthened, which is normally a function of the mouse control software, not the application. Ie, my Logitech mouse uses Logitech SetPoint. Microsoft Mice use MS IntelliPoint, etc.
Another possibility is that the mouse switches may be wearing out.