I have a problem with SharePoint Designer where I am in design or split view mode and the PlaceholderLeftNavBar keeps refreshing. When the refresh happens the LeftNavBar disappears and is replaced by rotating arrows and displays "Rendering in Progress" in the status bar notification area. The refresh takes place about every 30 secs. This makes it difficult to work in design or split view mode because the screen jumps around when working in these views. Sometimes SPD eventually ends up crashing. Anyone know how to turn this off?