protected int getRegion(MouseEvent e) {
			Insets insets = content.getInsets();
			JScrollBar hbar = scrollPane.getHorizontalScrollBar();
			JScrollBar vbar = scrollPane.getVerticalScrollBar();
			int vdim = 0;
			if (hbar != null && hbar.isVisible()) {
				vdim = hbar.getHeight();
			}
			int hdim = 0;
			if (vbar != null && vbar.isVisible()) {
				hdim = vbar.getWidth();
			}
			boolean nearRight = e.getX() >= content.getWidth() - insets.right - hdim;
			boolean nearBottom = e.getY() >= content.getHeight() - insets.bottom - vdim;
			boolean closeRight = e.getX() >= content.getWidth() - 20;
			boolean closeBottom = e.getY() >= content.getHeight() - 20;
			if (nearRight && nearBottom || nearRight && closeBottom || closeRight && nearBottom) {
				return REGION_SE;
			}
			else if (nearRight) {
				return REGION_E;
			}
			else if (nearBottom) {
				return REGION_S;
			}
			return REGION_NONE;
		}
A mouse listener that resizes the auto-completion list window
Ghidra/Framework/Docking/src/main/java/docking/widgets/autocomplete/TextFieldAutocompleter.java