waterfox has been doing since firefox stopped doing it, actually waterfox is doing right everything firefox does wrong:
Disabled Encrypted Media Extensions (EME)
Disabled Web Runtime (deprecated as of 2015)
Removed Pocket
Removed Telemetry
Removed data collection
Removed startup profiling
Allow running of all 64-Bit NPAPI plugins
Allow running of unsigned extensions
Removal of Sponsored Tiles on New Tab Page
Addition of Duplicate Tab option
Locale selector in about:preferences > General