How to change window size of `ASWebAuthenticationSession`?

Is there a way (in code or on the OAuth2 server/webpage) to specify the desired window size when using ASWebAuthenticationSession on macOS? I haven't found anything, and we would prefer the window to be narrower. For one of our users, the window is even stretched to the full screen width which looks completely broken…

How to change window size of `ASWebAuthenticationSession`?
 
 
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