Update documentation on DCACCOUNT

Corresponding core PR:
chatmail/core#7360

Author: link2xt

uri-schemes.md

@@ -161,16 +161,22 @@ https://i.delta.chat/#EEA98F87742EF2FD6C23677F1E1142828C202998&a=demo.fn8hk%40fi
 
 ### Syntax
 
-currently this only accepts a url that gives back account setup information as a json object.
-see the [mailadm](https://github.com/deltachat/mailadm) project for more details as this api was designed for use with burner account qr codes generated by mailadm.
+This scheme contains either the domain name of a chatmail server or an HTTPS URL.
 
-```
-DCACCOUNT:https://example.org/new_email?t=1w_7wDjgjelxeX884x96v3
-```
+If domain name is used, e.g. as `DCACCOUNT:example.org`,
+then the client should generate a 9-character alphanumeric lowercase username,
+e.g. `ipvzrws6x@example.org`,
+and a password that is at least 30 characters long,
+drawn from the full set of alphanumeric characters (`A-Z`, `a-z`, `0-9`).
+
+If URL is used, e.g. `DCACCOUNT:https://example.org/new_email?t=1w_7wDjgjelxeX884x96v3`,
+then the client should make an HTTP/1.1 GET request
+and receive account setup information as a JSON object.
+See the [mailadm](https://github.com/deltachat/mailadm) project for more details as this API was designed for use with burner account QR codes generated by mailadm.
 
 You may want to use [`DCLOGIN`](#DCLOGIN) instead, if you want a qr code containing login information for a single account.
 
-#### The http endpoint needs the following api:
+#### The HTTP endpoint needs the following api:
 
 ##### On Success