Download Firefox Developer Edition 148.0b4

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

Updated: January 21, 2026

Size: 159 MB

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159 MB · January 21, 2026

Firefox%20148.0b4.dmg

Previous versions More »

148.0b7 January 28, 2026 160 MB 148.0b5 January 23, 2026 160 MB 148.0b4 January 21, 2026 159 MB 148.0b3 January 18, 2026 159 MB 148.0b2 January 16, 2026 159 MB 147.0b9 January 02, 2026 155 MB