Note: Having searched the forum, I found that this is identical to a bug reported by Shadow.NET, but in that post the bug was dismissed as non-existent and the thread is now too old to revive: http://paintdotnet.12.forumer.com/viewtopic.php?t=3470
Description: Toggling the floating tool windows using the keyboard when there are no documents open causes Paint.NET to lose focus. Focus is passed to the next open application in Windows. Furthermore, Paint.NET also disappears from the Alt+Tab Task Switcher and does not reappear until the Paint.NET window recovers focus.
Severity: Minor
Reproducible: Always
Steps to reproduce:
1. Open Paint.NET and have at least another one program running (suggest you have another two programs running, so that the task list is well populated).
2. Close all images so that Paint.NET has no open images.
3. Using the keyboard, toggle the floating tool windows in an order such that when two floating windows are closed, open the first one then second one and then close the second one.
For example, when the Layers and Colors windows are closed, press F7 to open the Layers window, then F8 to open the Colors window, then F8 again to close the Colors window. (ie, F7, F8, F8 ).
Expected behaviour: The floating tool window closes.
Actual behaviour: The floating tool window closes, but also the Paint.NET application loses focus and the focus is passed to the next application in the task list. Paint.NET also disappears from the Alt-Tab Task Switcher until it receives focus again.
This bug can also be reproduced by using the keyboard only to toggle the floating tools windows via the options in the Window menu, but it does not occur if the mouse is used.
Tested: Paint.NET v3.08 and v3.10 beta, Windows XP.