Controls not correctly repainted 5 Beta 121

[rjp74]

Using v5 beta 121, on Windows 7, I observe that the group of media controls is not repainted after choosing menu item "open project" and the open dialog covers these controls. When the open dialog is closed the controls are no longer visible. They can be repainted by running the mouse over the area where they should be.
This seems to be true of some other controls as well. I loaded a two track project and was surprised to see a number of other tracks. They disappeared when I rolled the mouse over them though.