Select the Triple Bar menu at the top right of your screen.
Scroll to the bottom of the Settings page and select Show Advanced Settings.
Under Privacy select Site Settings.
In Firefox, type about:config in the address bar, then press Enter.
Select the I accept the risk! button.
Click on the O in the top left corner of your browser.
Additionally, you can open a new tab and press alt and p to open your settings.
Scroll down to Site Settings.
Click the [...] menu button to the upper right in the header bar.
Select Cookies and site permissions.