The Developer or Debug Mode gives you access to extra and advanced tools.
Through the Settings application
Activate the developer mode (with assets) is used by developers; Activate the developer mode (with tests assets) is used by developers and testers.
Once activated, the Deactivate the developer mode option becomes available.
Through a browser extension
Through the URL
In the URL add
?debug=true after web.
?debug=assets and activate the mode with assets.
Locate the mode tools
The Developer mode tools can be accessed from the Open Developer Tools button, located on the header of your pages.