I have a couple of users interested in using Blurb's "Bookify" flash app for creating photobooks (although that link may redirect to the download for the desktop native app if Flash isn't installed).
Both users have logins on a (high-end) machine running Linux (Debian "Stretch" 64bit) with Firefox (ESR) 52.4.0 and Adobe Flash 27.0.
For one user, the "Bookify" application appears to run absolutely fine.
For the other user (on the same machine, using the same browser and flash version!), it shows its startup progress bar dialog... but that bar freezes at the 99% point forever.
I've tried clearing all "blurb" cookies, clearing browser cache... but nothing seems to improve situation for that user. Whereas the other user continues to have no problems when they attempt to use the app.
Any ideas how to "unstick" it?
Someone posted the same/similar problem on Blurb's FB page a while ago; no solution posted there but I'll try messaging them myself. (There's also another mention from around the same time here).