FIX: modal windows disappeared when dragged to a different space - #6
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lanewei120 merged 1 commit intoSep 10, 2026
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Why
The commented-out original logic is [parentNSWindow addChildWindow:m_macWindow ordered:NSWindowAbove].
addChildWindow:ordered:establishes a parent-child window relationship at the AppKit level; the child window and parent window are bound to the same Mission Control Space, and the drawing context (backing store) is associated with the screen where the parent window resides.When the parent window remains on Screen A and the modal child window is dragged to Screen B, AppKit attempts to maintain the constraint that the child window stays above the parent. However, since the parent window is not present on Screen B to serve as a reference, the window server cannot establish the necessary relative compositing relationship there; consequently, the child window is either repositioned back near the parent or fails to composite on Screen B entirely, appearing blank or disappearing.
How
By removing the
addChildWindowcode, the modal dialog becomes an independent top-level window, no longer bound to the parent window's screen, position, or Space.