Question email login plesk only with username

[grazer75]

Hi,
on another server it was possible to check emails with only the user name, on a other server with obsidian now it only
works by full email adress as username, can this be changed somehow / somewhere?

 

[grazer75]

Update i guess it can be changed with

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and using this
„auth_username_format=%{if;%d;eq;hostname.startdedicated.de;%Ln;%Lu}“
but can i create there this without replacing the whole configuration or will it be loaded only additionally?