Responsive Design Mode
Related Topics
Page Inspector
Web Console
JavaScript Debugger
Network Monitor
Performance
Application
Responsive Design Mode
Accessibility Inspector
More Tools
Memory
Storage Inspector
DOM Property Viewer
Eyedropper
Screenshot
Style Editor
Rulers
Measure a portion of the page
View Source
Connecting the devtools
about:debugging
Connecting to Firefox for Android
Connecting to iframes
Connecting to other browsers
Debugging the browser
Browser Console
Browser Toolbox
Extending the devtools
Settings
Tips
Release notes