Open Firefox
Click the menu button in the top-right corner
Select Settings
Click Privacy & Security
Scroll to Cookies and Site Data
Click Clear Data
Check Cached Web Content
Click Clear
Confirm by clicking Clear Now
Open Firefox
Click the menu button in the top-right corner
Select Settings
Click Privacy & Security
Scroll to Cookies and Site Data
Click Clear Data
Check Cached Web Content
Click Clear
Confirm by clicking Clear Now