Don't allow MoveAction when dragging colors from color buttons, allows dragging colors from QGIS and dropping them into GIMP/Inkscape

Author: nyalldawson

src/gui/qgscolorbutton.cpp

@@ -185,7 +185,7 @@ void QgsColorButton::mouseMoveEvent( QMouseEvent *e )
   //set as drag pixmap
   drag->setPixmap( QPixmap::fromImage( colorImage ) );
 
-  drag->exec( Qt::CopyAction | Qt::MoveAction );
+  drag->exec( Qt::CopyAction );
   setDown( false );
 }