For my own info –
- Offline installer for Firefox – https://www.mozilla.org/en-US/firefox/all/
- Offline installer for Firefox Beta – https://www.mozilla.org/en-US/firefox/beta/all/
- Offline installer for Firefox Developer Edition – https://www.mozilla.org/en-US/firefox/developer/
Good to have these in case you are not connected to the Interwebs and wan’t to install Firefox.
Also, this link on how to set a proxy in Firefox for all users.