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Description of Problem:
There is a problem with executing Hide() command (or setting Visible property to false) on Winforms window under Linux. I made a simple app, which can be shown or hidden using trayicon click. The problem is, that hiding window fails, when the window is minimized to the taskbar. The window does not hide - the button remains in the taskbar. When clicked, only window border appears (content is "transparent"). Clicking on trayicon again (running Show() method) restores window content. When trying to hide when window is in Normal state, it does disappear correctly.
Steps to reproduce the problem:
1. Create simple Winforms application with a tray icon or second window - to be able to Show() and Hide() main form
2. Minimize main form to taskbar and try to Hide() it (or try to set Visible=false, does not matter)
Window persists in taskbar. When clicking on taskbar icon, an erroneous window appears (only window borders, no contents)
Hide window and taskbar button correctly, like .NET does under Windows.
How often does this happen?
Every application run.
I tried to hide the window button using ShowInTaskbar property. It does hide the taskbar item, but the transparent "zombie" window (now even without borders) still exists and can be accessed under KDE using Alt+Tab window list.
Tried to restore (WindowState=WindowState.Normal;Refresh();) the window before hiding it. This helps but only during first hide. With this "hack" I can hide the window and restore it correctly, but when after restore I try to hide it again, the same error still happens.