sImgurUploader only works with an anonymous API account so I'd choose the "Anonymous usage without user authorization" option (and leave the second part blank).
I'm not allowed to leave part two blank :-(
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So,
I tried 1b (see post #35) and got this:
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which looked to me that, for authorisation, I type
Authorization: Client-ID xxxxxxxxxxxxxxxxxxxxxx (xxxxx... being the client ID given)
no joy, so I tried variations with the 'Application name'; then with both Client ID's, and then everything (I think

) without 'Authorisation' before - tbh I made the mistake of not keeping track of everything I tried ...

Any ideas

edit // here's the link shown in image #2 -
https://api.imgur.com/oauth2edit #2 // maybe I have to give it a bit of time (and make a sacrificial offering

) before it will work?