Dear experienced and knowledgeable people of MacRumors, I've just started downloading apps on my new MBA with Firefox being one of them. However, unlike the other apps I've downloaded, the Firefox icon appears to be a barred app instead (see attached image). There are no problems with it in Launchpad or Dock, just the Apps folder. Does anyone have any idea why and how I may go about fixing this?
Thank you very much in advance

Thank you very much in advance