How to set up Mozilla Firefox on Mac computer?

When you run Mozilla Firefox for the first time after the installation, it will guide you to go through the setup process as shown below.

1. Run Mozilla Firefox from the Launchpad. You see the security warning:

"Firefox" is an application downloaded from the Internet. 
Are you sure you want to open it?

2. Click "Open" to open it. You see the primary browser setting:

Make Firefox your primary browser?

Keep Firefox at your fingertips - make it your default browser 
and keep it in your Dock.

3. Check "Don't show this message again" and click "Not now". You see the "Open up an amazing internet" optional setup step.

4. Click "Skip this step". You see the "Make Firefox your go-to browser" optional setup step.

5. Click "Skip this step". You see the "Lightning-fast setup" optional setup step.

6. Click "Skip this step". You see the "Choose the color that inspires you" optional setup step.

7. Click "Skip this step". You see the "Hop from laptop to phone and back again" optional setup step.

8. Click "Skip this step". You see the "You’re helping us build a better web" optional setup step.

9. Click "Skip this step". You see Firefox ready for you to browse the Internet.

⇒ Mozilla Firefox Personal Profiles on Mac

⇐ Install Mozilla Firefox on Mac Computer

⇑ Using Mozilla Firefox on Mac Computer

⇑⇑ Firefox - Frequently Asked Questions