If you have to deploy Firefox or Chrome in your environment, use the Enterprise versions for more stability.
https://mozilla.org/en-US/firefox/organizations/all/
https://www.google.com/intl/en_us/chrome/business/browser/admin/
Firefox installation: Firefox Setup 38.4.0esr.exe -ms
Chrome installation: msiexec /i googlechromestandaloneenterprise.msi /qn