User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:39.0) Gecko/20100101 Firefox/39.0 Build ID: 20150630154324 Steps to reproduce: I'm using Mac OS X 10.7.5 Went to www.cryptograms.org At upper left, under the picture, I clicked on "Play". A puzzle appeared. At the bottom, I clicked on "Hint me!" (it only gives vowels) until a dialog box popped up saying no more hints were available. I clicked on the "OK" button in the dialog box to dismiss it. Actual results: Most of the time the dialog box goes away. Sometimes Firefox hangs and I have to "Force Quit" it. You have to get hints until the dialog box pops up to see the occasional problem. Expected results: The dialog box should have gone away.
Is it reproducible with a fresh profile? https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles
I can't get it to fail any more. Perhaps the problem went away when I went to 39.0 of Firefox. Please close the bug. I don't know how to do that.