Bug 130841

Created attachment 158077 [details]
Document with onLoad resize macro

The origin of this problem is the native menu bar, which results in a different "client area" / drawable area in comparison to the frame geometry from LO's POV. This isn't really supported in VCL - or I missed some interface. At least kf5 and gtk3 currently use a hack to do this. No other backends uses native menu bars inside the frame.

It's also easily verifiable by changing the user interface to tabbed or resizing the window.

The attached macro should just non-resizes the Window on load via:

Sub Main
  window = StarDesktop.currentComponent.CurrentController.frame.ContainerWindow
  rect = window.getPosSize()
  window.setPosSize(0, 0, rect.width(), rect.height(), com.sun.star.awt.PosSize.SIZE)
End Sub

But it doesn't. At this point the kf5 window shows two problems:

1. the window shrinks in height by the menu bar height
2. the window doesn't paint its status bar correctly, as that is now outside the window

The first one is a kf5 only problem, while the 2nd one also happens for gtk3. Actually gtk3 had the same first problem, until commit e3a002c53a54 ("get native gtk widgets in sidebars working") forced a relayout of weld'ed native widgets to fix an other problems with the sidebar. That corrects the "hack" again.

For kf5, the first problem can be fixed by applying the hack from: https://gerrit.libreoffice.org/c/core/+/89202

FWIW: this bug was exposed by the WollMux Java extension, where scrolling after the resize also creates massive drawing artifacts. I didn't figure out what else it interfering here.