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In the admin area, to create a custom block, I go to:
Structure, Block layout, + Add custom block.
Once I create the custom block in the UI, I see a textarea field called "Body" where I can enter content.
How can I dynamically render the node author's name and profile picture in my custom block. I know I can type it in, but I would like to be able to insert some code (PHP, Twig or token) so that it pull's the author's name and profile image dynamically and prints it on the block. I do not want to use a views block, but a custom block instead.