https://core.tcl.tk/tk/info/5a5abf71f9
--- macosx/tkMacOSXDraw.c.orig
+++ macosx/tkMacOSXDraw.c
@@ -1686,10 +1686,11 @@
 TkMacOSXRestoreDrawingContext(
     TkMacOSXDrawingContext *dcPtr)
 {
     if (dcPtr->context) {
 	CGContextSynchronize(dcPtr->context);
+	[[dcPtr->view window] setViewsNeedDisplay:YES];
 	[[dcPtr->view window] enableFlushWindow];
 	if (dcPtr->focusLocked) {
 	    [dcPtr->view unlockFocus];
 	} else {
 	    CGContextRestoreGState(dcPtr->context);