Hi

I should be able to help with this.

If you press F12, the dev tools should open at the bottom of the screen. I hope that this helps.

Thank you Seburo. I had looked through DEV tools before but had missed on the Network tab, the circle with a cross through it for request blocking. I think this will do what I need. I had hoped there would be an easier way to go online/offline with the new Firefox. This would help with PWA development and testing.

Great, glad to hear it.

You may want to learn more about our dev tools and Firefox Developer Edition at https://www.mozilla.org/en-GB/firefox/developer/

For anyone else that needs to go online/offline quickly, right click the top toolbar (where tabs are) > check 'Menu Bar' > File > Work Offline.

Thank you for your feedback, I hope that you like using Firefox dev tools.