You have been disconnected (10.2.7 client Arctium Launcher)

Using Arctium WoW Launcher
On startup it detects the name I set in the config.

calling the bnet login from the client machine with that name gives a plausible result:
{“type”:“LOGIN_FORM”,“inputs”:[{“input_id”:“account_name”,“type”:“text”,“label”:“E-mail”,“max_length”:320},{“input_id”:“password”,“type”:“password”,“label”:“Password”,“max_length”:128},{“input_id”:“log_in_submit”,“type”:“submit”,“label”:“Log In”}],“srp_url”:“https://dragonflight.local:8081/bnetserver/login/srp/”}

(name in srp_url is also what Arctium finds)

Connection.log gives:
9/16 20:52:52.088 Connection Initialize
9/16 20:53:01.399 Glue Start Login
9/16 20:53:01.399 BattleNet Attempt Logon
9/16 20:53:01.414 BattleNet Front Disconnected
9/16 20:53:01.414 Glue Fatal Error: 1016

for each attempt

I verified that the cert is accepted by the system with wget:
wget https://dragonflight.local:8081/bnetserver/login/
gives correct result

wget https://192.168.2.43:8081/bnetserver/login/
gives cert error

So I also confirmed that wget does usually care for the cert by default as I call it.

Could it be that I did not sufficiently clean out the client? (Backed up my client before updating to WW, it’s the client data I used to play om official servers before)
I deleted:
WTF
Cache
Logs
Interface

and set portal in the new WTF

Arctium_cropped

Running it under Proton Experimental

Is it possible that Arctium launcher has a bug where it refuses to accept certain certificates no matter what the system says?

Can’t test it because during my attempt to test it I got the reminder that my router does not support connecting back via my external IP from the local network.

this came up as I was trying different parameters and if I turn of dev mode it complains about the certificate and shuts down.

Does Arctium bring its own root certificates? Does it use the browser settings?

Anyone here able confirm or deny this?