Disappearing TAdvToolBarButtons

Delphi 10.4.1

I have 4 AdvToolBars on a AdvDockPanel. One toolbar is for the menu and the other 3 contain AdvToolBarButtons, Click in a toolbarbutton to display a form....exit from the form and all is still displayed correctly. The problem I have is that on some screens (at this stage mobile devices such as laptops or surface tablets) the extreme right end button on the toolbar (from which the button was clicked to display a form) disappears after closing the form. Further use of the remaining buttons will not make any further buttons disappear. Displaying the same form from the main menu will not make the button disappear....only when using the toolbarbuttons.

Can you please advise as to what might be happening here.


Bill Zwirs

So far I could not reproduce this. I can't see anything in recent changes in this area at all.
Can you reproduce this with any of the demos included?