User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.8) Gecko/20050511 Firefox/1.0.4 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.8) Gecko/20050511 Firefox/1.0.4 confirmation: steps to reproduce: - press CTRL+O - select a .swf file from - press OPEN-button then way a (normal) or b (even worse): a) - firefox will ask wether to open with a specific program or to download b) - select "Other..." within the "Open With" dropdown - a dialog called "Choose Helper Application" will be opened - select firefox.exe to tell firefox it should open .swf files - press OPEN-button - check checkbox "Do this automatically for files like this from now on >> firefox will start to open tab after tab after tab until your system crashes. this is the "even worse" case. Reproducible: Always Steps to Reproduce: 1. see before Expected Results: the software should simply open the .swf file (it's mimetype is shockwave/flash) as if it would done while requested by a http:// url.

This is a dupe. Picking "firefox.exe" as the external app really doesn't work so well as some people seem to think it will.

Case B is Core bug 167320?

case A is bug 279327 comment 1 case B is bug 167320 *** This bug has been marked as a duplicate of 167320 ***