The initial version was simply a div at the bottom of the page that would print window.onerror events and anything sent to console.log. The functionality was very limited, but it solved our problem of being able to identify errors. Since then we have cleaned up the UI and added functionality.
Current features include:
- Display console output (log, info, warn, error)
- Evaluate expressions from console input
- Hide or show the tool via keyboard shortcut
For security reasons the console input does not execute arbitrary code, it can only parse and evaluate variables (e.g. window.location).
Potential features for the future include:
- DOM explorer
- Network request viewer
- (Any other Dev Tools features)
The project is still very young and the functionality that it has now is just the tip of the iceberg. The end goal is ultimately to provide all the functionality of modern browser’s Dev Tools without the need for a modern browser.