421 Unknow

After upgrading Horizon to 2306 2212.1 or 2111.1 we see this message when trying to connect from UAG

In the log, I see this error:

2021-09-24T22:05:34.737-07:00 ERROR (1B08-1A58) <SimpleDeamonThread> [h] (ajp:admin:Request190) Unexpected Origin: https://newname.net

2021-09-24T22:05:34.738-07:00 DEBUG (1B08-1A58) <SimpleDeamonThread> [v] (ajp:admin:Request190) Response 404 Not Found [close]

The fast solution is to set allowUnexpectedHost to true on the locked.properties file. This is located on each connection server in     c:\program files\vmware\VMware View\Server\sslgateway\conf. and restart the horizon connection services

Cross-Origin Resource Sharing (CORS) with Horizon 8 and loadbalanced HTML5 access. (85801) (vmware.com)

Error 421 while connecting to Horizon via HTML Web Console after an upgrade to 2306,2111.1 or Later (93915) (vmware.com)

421 Unknow