How to Stop Your FireFox Accesses detectportal.firefox.com

(1) Open a new tab/window, copy

and paste it in the address bar and press Enter/Return.

(2) Copy

and paste it into the search box above the list.

(3) Click/Double-click the preference column of 'network.captive-portal-service.enabled' to switch the value from true to false.

Feb 25, 2019　Added: Reference

"How to stop Firefox from making automatic connections"

Jan 19, 2024　Added: Reference

"Why Firefox connects to googleusercontet.com within 2 minutes of it reaching the internet?"

Added: Jun 23, 2024:　RL loves "LibreWolf" lately.

"LibreWolf" is a custom version of Firefox, so, I can also use Add-ons for "FireFox".

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I love "LibreWolf" lately.