Give your phpBB users a unique default avatar like Google Mail, Wordpress etc. PIA its an extension that requires at least phpBB version 3.2.1
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This extensions as per the Lite version uses the API located here: https://github.com/LasseRafn/ui-avatars
Copy the extension to phpBB/ext/threedi/pia
Go to "ACP" > "Customise" > "Extensions" and enable the "phpBB Initial Avatars" extension.
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