If you'd like to follow developments on this the Firefox bug seems to be this one : https://bugzilla.mozilla.org/show_bug.cgi?id=1749908
I'm confirming simply deactivating all Firefox telemetry is enough:
If you have changed the
network.http.http3.enabled setting as told above, you can reset it to it's initial value (
Restart Firefox to finish.
Someone from Firefox posted :
Our current suspicion is that Google Cloud Load Balancer (or a similar CloudFlare service) that fronts one of our own servers got an update that triggers an existing HTTP3 bug. Telemetry was first implicated because it's one of the first services a normal Firefox configuration will connect first, but presumably the bug will trigger with any other connection to such a server.
@tcit Not sure this is enougth as per https://bugzilla.mozilla.org/show_bug.cgi?id=1749908#c21 you can also trigger this issue with Google Cloud http/3 load balancer.
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