Firefox/Iceweasel

Install an extension globally

  1. Download and copy the .xpi file into the <installation directory>\extensions folder (<installation directory> on Debian is /usr/lib/iceweasel/browser)
  2. Extract the correct name using this guide
  3. Create a dir with the previous name and extract the xpi inside
  4. Remove the xpi

Disable add-ons manager

  1. Go into the <installation directory> folder (<installation directory> on Debian is /usr/lib/iceweasel/browser)
  2. Append the following row to chrome.manifest
    override chrome://mozapps/content/extensions/extensions.xul data:text/html,Disabled

Tweaks

Setup your own Firefox account and sync account

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