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Why Does Firefox Have a Launch Delay When I Set My Firewall to Block All Internet Traffic But HTTP?

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  • Nzaghachi ikpeazụ nke BeKind

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If I set my firewall to block all traffic but HTTP/HTTPS then proceed to launch Firefox, Firefox will delay ten to fifteen seconds before launching. In my experience with other programs, such a delay usually means the software is trying to connect to a server somewhere and is timing out once it determines that it cannot connect. I guessed that perhaps it might be Firefox searching for updates or reporting data (telemetry, health & crash data) but I disabled the update check and the data-reporting and the delay is still present. What is likely causing this delay?


Windows XP Firefox 35.0 Delay occurs even when using a clean profile (default settings and no plugins installed).

If I set my firewall to block all traffic but HTTP/HTTPS then proceed to launch Firefox, Firefox will delay ten to fifteen seconds before launching. In my experience with other programs, such a delay usually means the software is trying to connect to a server somewhere and is timing out once it determines that it cannot connect. I guessed that perhaps it might be Firefox searching for updates or reporting data (telemetry, health & crash data) but I disabled the update check and the data-reporting and the delay is still present. What is likely causing this delay? Windows XP Firefox 35.0 Delay occurs even when using a clean profile (default settings and no plugins installed).

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hi, maybe the following article can give you some more clues: How to stop Firefox from making automatic connections

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philipp said

hi, maybe the following article can give you some more clues: How to stop Firefox from making automatic connections

Thanks for the link but I tried everything on the page and the delay is still present. Also, the delay is a bit longer than I thought. It's usually 20 seconds.