Multiple Instances of Web App Error
When I open a particular web app on Safari, I usually (not always) get an error message saying "Application is already opened! Multiple instances of this application using tabs or new window is not supported." However, I know that I don't have any other versions open. This doesn't happen and the app works fine using Chrome. How can I get the app to work on Safari?
MacBook Pro (Retina, 13-inch, Late 2013), OS X Yosemite (10.10.2)