Add QUIC version 43 to LSWS 5.2.8

In LSWS Admin I have the QUIC Versions parameter not set and the header shows
alt-svc: quic=":443"; ma=2592000; v="35,37,38,39"
The HTTP/2 and SPDY indicator says http2 enabled and no green icon :/
But here, I can see that this forum has SPDY+quic/43
alt-svc: quic=":443"; ma=2592000; v="35,39,43"
How can I enable QUIC version 43 and why it's not enabled by default?
Is it safe to upgrade? I would like to test the criu features also but I'm in a production server :/
I've been thinking for a couple of weeks that something was wrong with my QUIC configuration
I have the 68.0.3440.42 version (Beta channel I think) and it seems that only wants the 43 version of QUIC
I have CSF with 443 udp ports open and was working a few weeks ago (tested with the directions here).
I'll test the RC, you're right, I can downgrade If things go wrong
Thanks a lot for your help mistwang