Hey folks, anyone else come across this?

Google chrome.exe 124 and Edge Chromium cannot reach Webserver behind IPS/proxy [cipher X25519Kyber768] - www.butsch.ch :

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The problem has started around 22.04.2024 and is growing.

This could effect you if:

You run or someone else runs a Webserver or any service with https / SSL / TLS 1.3 behind:

1. PPPoE WAN
2. Celuar Media like G4/G5 networks (Depending on SIM ISP/provider > One SIM card works the other SIM not OVER same GX routers > People reported who have DUAL IM for data)

The new cipher X25519Kyber768 that is activated on client side with the Chrome 124 seems at the end to generate larger paket header and old friend the MTU-Size [maximum segment size (MSS)] comes into play again.

It will affect your user who use chrome to access a webserver, which has that problem.
......

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I spent some time trying to track this down. I use Sophos XG (virtualised). Oddly the problem was only occurring for a few destinations. I still can't explain that.