For starters I wouldn’t co all the paranoic about Mozilla getting some telemetry as most of them are not about privacy. Some of you probably will want to disable those also this could help speed up Firefox a bit.
Get into internal settings by typing `about:config` in url bar and turn all of these to false by double clicking
browser.newtabpage.activity-stream.feeds.telemetry browser.newtabpage.activity-stream.telemetry browser.ping-centre.telemetry toolkit.telemetry.archive.enabled toolkit.telemetry.bhrPing.enabled toolkit.telemetry.enabled toolkit.telemetry.firstShutdownPing.enabled toolkit.telemetry.newProfilePing.enabled toolkit.telemetry.reportingpolicy.firstRun toolkit.telemetry.shutdownPingSender.enabled toolkit.telemetry.unified toolkit.telemetry.updatePing.enabled experiments.activeExperiment experiments.enabled experiments.supported network.allow-experiments
I wouldn’t recommend you to do this on any non-stable channel release as those are heavy related with telemetry and making Firefox great.