If I have [Adobe Flash Player] installed, [Mozilla Firefox] frequently occurs an error and shutdown(forced turn off/exit) / If I remove the [Adobe Flash Player], [Mozilla Firefox] doesn't occur shutdown(forced turn off/exit).

If I have [Adobe Flash Player] installed, [Mozilla Firefox] frequently occurs an error and shutdown(forced turn off/exit) / If I remove the [Adobe Flash Player], [Mozilla Firefox] doesn't occur shutdown(forced turn off/exit).

They are all latest version. (2015-06-01)

[Adobe Flash Player] version 17.0.0.188

[Mozilla Firefox] version 38.0.1

Therefore, I don't use or install [Adobe Flash Player(latest version)].

Where can I get [Adobe Flash Player version 11]? (or older version than Adobe Flash Player 15)