When I try to use the visual composer to edit/build a page, the widget menu pops up, but the entire screen has a dark grey overlay, and none of the buttons on the pop-up menu are responsive. I can only go back from this page. I have tried uninstalling the theme, deleting all plugins, reinstalling the theme, and checking for updates. Nothing seems to remedy the grey overlay.
What would have caused this, and is there some way I can recover the use of VC?