QUIC/H3 doesn't work over tailscale due to MTU size

It seems that QUIC fails to work over tailscale when using the exit node. I've installed QUIC Indicator in chrome (https://chrome.google.com/webstore/detail/quic-indicator/dghiicffobcmljfmlaedpmpmgpnjcabc) and I never see websites I know that offer QUIC/H3 using the protocol, but I do when I turn off exit node. Quick test is:

Make sure QUIC Indicator is installed
Turn on tailscale w/ exit node
Go to https://cloudflare-quic.com/
Set exit node to None
Go to https://cloudflare-quic.com/

Reproduce the reported behavior with Tailscale using an exit node, the QUIC Indicator extension, and https://cloudflare-quic.com/, then compare it with the no-exit-node case. No source files, tests, or entry points are named, and the issue does not define the expected fix; determine how the MTU affects QUIC/H3 traffic and establish a focused regression test before considering the work done.

Written by the indexing model from the issue text.