I downloaded three versions of Firefox: 3.6, 3.5 and 3.0 from Mozilla ftp server. Then I created three profiles, e.g:
firefox -no-remote -CreateProfile firefox-3.5
Then I tried to run it:
./firefox -no-remote -P firefox-3.5
but it failed with the error:
./firefox-bin: symbol lookup error: ./libxul.so: undefined symbol: _Z19js_obj_defineGetterP9JSContextjPi
(firefox-bin:4034): GLib-CRITICAL **: g_hash_table_insert_internal: assertion `hash_table != NULL' failed
Actually it worked in 10.10. I dropped in on Mozilla’s Firefox IRC channel and one dude told me he had never seen this bug before so I suppose that it is Natty issue.