Un Firefox "nettoyé". Je cite:
« Features:
   - 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 »

Accessoirement, il vous permet de faire tourner les anciennes extensions Firefox et d'installer des extensions non signées. Ça peut servir.