WhatsApp error - "There is no application set to open the URL about:blank."
MacBook Air (11-inch Mid 2013), OSX 10.12.6
Remove old version of "Desktop WhatsApp" and get a new version of "WhatsApp" from the App Store.
Remove old version of "Desktop WhatsApp" and get a new version of "WhatsApp" from the App Store.
So. I was encountering this too, only with WhatsApp. Finding no answers in support communities, I uninstalled (sent to Trash) my Desktop app and reinstalled it....and the problem is solved.
Download from Itunes NEVER from the NET.
WhatsApp error - "There is no application set to open the URL about:blank."