Canvas Capture is a Firefox extension designed for web developers looking to capture video streams from HTML canvas elements easily. This free tool allows users to click on an animated canvas element on a webpage and start recording with a simple browser action. The extension displays a list of available canvases along with pertinent details, enabling users to select the desired one for capturing. Once the recording is complete, users can stop the capture and download the video file directly.

The captured videos are outputted in the webm format, utilizing the browser's codec choice, typically VPX. The underlying technology employs the MediaRecorder, MediaStream, and Blob APIs, ensuring a smooth capture process without the need for network access. Canvas Capture is an invaluable tool for developers looking to create visual content from web applications.