Firefox Developer Edition 67 Apr 2026

: Added support for importing JavaScript modules dynamically. 4. Privacy & Security Understanding in depth the profile per installation feature

: The system for selecting the dedicated default profile was standardized to match other versions of Firefox, moving away from specific profile naming like "dev-edition-default". 2. Performance Enhancements

: Developers can now track all CSS modifications made within the browser and copy either the full set of changes or individual rules directly. JavaScript Debugger Improvements :

: If system memory drops below 400MB, the browser automatically suspends idle tabs to free up resources, reloading them only when clicked. 3. Developer Tool Updates

: Provides higher fidelity for pausing execution at specific locations within a single line of code.

: A new panel for streamlined debugging of web workers.

: This version marked the gradual release of WebRender , a GPU-based 2D rendering engine written in Rust. It shifts page rendering from the CPU to the GPU, making the browsing experience significantly smoother.