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Firefox has way too slow DNS resolution

w.richert
w.richert
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The initial handshake takes typically a couple seconds in Firefox, while it takes in Chrome or Safari typically < 1s to display the first content.

Here an example of opening firefox.org: https://share.firefox.dev/3jpZRG4

I've tried all the recommended procedures without any success (personal mode, disabling extensions, starting with clean profile, ...)

Even this form I had to send twice because there was a timeout when sending the data up.

My internet connection is always > 30Mbps, so that should not be a problem.

The initial handshake takes typically a couple seconds in Firefox, while it takes in Chrome or Safari typically < 1s to display the first content. Here an example of opening firefox.org: https://share.firefox.dev/3jpZRG4 I've tried all the recommended procedures without any success (personal mode, disabling extensions, starting with clean profile, ...) Even this form I had to send twice because there was a timeout when sending the data up. My internet connection is always > 30Mbps, so that should not be a problem.

All Replies (2)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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You can check the Network Monitor to see if content is blocked or otherwise fails to load.

If necessary use "Ctrl+F5" or "Ctrl+Shift+R" (Mac: Command+Shift+R) to reload the page and bypass the cache to generate a fresh log.

You can try to disable IPv6 (check for other possible causes as well).

Thomas M. Beaudry
Thomas M. Beaudry
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The other browsers have a faster fallback to IPv4 so it is possible that his IPv6 DNS is not configured correctly. That is what I would check first. Simply turning off IPv6 without checking out the problem is like cooking all your food in a microwave because you have problems operating the stove...