400 errors after upgrading to 1.14.0

[kpuscas]

Our service uses 2-way ssl with our clients connecting to our systems. With
each new client we add their intermediate and root CA chain to the
concatenated certificates file used by ssl_client_certificate. We recently
upgraded to 1.14.0  (and the included modules) and now some, but not all of
our customers are unable to connect getting 400 errors. We've tried changing
the order of the certificates in the concatenated file but that didn't help.
It is happening across different certificate chains but not all. And all of
them worked fine prior to the upgrade.  

Has anyone else encountered this or is there something we should be doing
different in how we set up these certificates?

Thanks

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,281315,281315#msg-281315