Download Firefox Developer Edition 142.0b9

Get the latest features, fast performance, and the development tools!

Updated: August 10, 2025

Size: 148 MB

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148 MB · August 10, 2025

Firefox%20142.0b9.dmg

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142.0b9 August 10, 2025 148 MB 142.0b8 August 09, 2025 148 MB 142.0b7 August 06, 2025 148 MB 142.0b6 August 03, 2025 149 MB 142.0b5 August 01, 2025 149 MB 142.0b4 July 30, 2025 149 MB