This post will provide a high level overview of changes coming up in the next Firefox ESR. This list is primarily focused on changes that will impact enterprise users. It is not intended to be an exhaustive list. For a list of all the changes, see the release notes links.

Note: Firefox Hello and Encrypted Media Extensions will NOT be part of the ESR.

Firefox 32

• New HTTP Cache
• Support for public key pinning
• Changes to main context menu
• Release Notes (32.0, 32.0.1, 32.0.2, 32.0.3)

Firefox 33

• Updates to one word searching
• Release Notes (33.0, 33.0.1, 33.0.2, 33.0.3)

Firefox 34

• New search UI (US only)
• Firefox Hello
• Theme Switching in Customize mode
• Ability to close Firefox when presented with "Firefox is already running" dialog
• Release Notes (34.0, 34.0.5)

Firefox 35

• Firefox Marketplace Menu and Button
• New Search UI in more locales
• Release Notes (35.0, 35.0.1)

Firefox 36

• HTTP/2 support
• Release Notes (36.0, 36.0.1)

Firefox 37

• Heartbeat user rating system
• Release Notes (37.0, 37.0.1, 37.0.2)

Firefox 38

• Preferences in tabs
• Release Notes (38.0)

My plan is to have a new CCK2 beta that coincides with the Firefox 38 release that will allow for disabling some of these new features. It's a beta because it also has the new code for no longer using the distribution directory.

If I missed something, please post it in the comments.

https://mike.kaply.com/2015/05/05/firefox-esr-38-overview/