What size resource icon and how to install

[Alvin63]

Just a question about resource icons. Is there an ideal size for uploading them? eg 500 x 500 or 200 x 200? ie would a smaller file size be better to reduce "load"?

Also, I have been uploading these manually every time I post a resource. Is this the correct way? I vaguely remember a couple of years ago, seeing something about the way to do it is upload the icon somewhere so it automatically uploads to a new resource (but can't find that post).
What size resource icon and how to install

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