The RoLLing cOde

As developing ActionScript projects, one have to frequently switch between different Flash versions and test. Here is a tip for Mac OSX ( also works on Windows I think ) to install multiple versions of Flash Player plugins for Firefox.

When Firefox starts, it scans for plugins in 3 sets of directories:

1. General plugin directory for current system and user, e.g.
   /Library/Internet Plug-Ins/
2. Plugin directory for current application executable file, e.g.
   /Applications/Firefox.app/Contents/MacOS/plugins/
3. Plugin directory for current profile, e.g. 
   ~/Library/Application Support/Firefox/Profiles/fw9q5h64.default/plugins

Then it will
sort by modification time
, dedupe and load all the plugins.

Now you get the trick:

1. Extract the desired firefox plugin files (
   e.g. Flash Player.plugin
   and
   flashplayer.xpt
   on Mac ) from Flash plugin installer or copy from installed directory ( e.g.
   /Library/Internet Plug-Ins/
   on Mac )
2. Copy these files to your favorite firefox app or profile directory
3. use the command
   
   
      touch -t 201603150101.01

   Flash Player.plugin

   flashplayer.xpt

   to make the mtime larger than the one in the general directory.

4. repeat above steps for all flash versions you want.

Update: you should check “Open using Rosetta” when playing Flash 8 or earlier with Firefox on Mac.