Firefox 57 Annoyance fixes

1. Stop Autoplay
about:config > media.autoplay.enabled = False

2. Remove Pocket
about:config >

browser.toolbarbuttons.introduced.pocket-button=false
extensions.pocket.enabled=false
extensions.pocket.api=api.example.com
extensions.pocket.site=example.com
extensions.pocket.oAuthConsumerKey = Random Bytes from random.org (The
sequence is 5 digits - 24 digits)

3. Install Cookie Auto Delete (in place of Self Destructing Cookies)
Once installed, activate its options from settings.
Then enable Auto-Clean (Active) mode.