Answered: Follow up: How to disable the viewing of user profiles? - plugin broken on 1.8.5?

There are a few things to note.

1. The plugin that is linked in the link you posted in your question is this one: https://github.com/Kuddus95/lock-user-profile. The link you are posting in your comment is this one: https://github.com/pedjas/q2a-hide-users-list. That's why I said the behavior you mentioned in the question can't be achieved with the original plugin.

2. You seem to be using an unreleased version of Q2A. You downloaded the code from the dev branch in the repository. You should use either the master branch or navigate to https://github.com/q2a/question2answer/releases and download the latest one.

Download the right version of Q2A and install it again. Then make all tests again.

3. I believe you will still face one more issue. I'd remove function qa_get_avatar_blob_url() and replace it with the function below:

function qa_get_user_avatar_source($flags, $email, $blobId) {
    return qac_approved_user()
        ? qa_get_user_avatar_source_base($flags, $email, $blobId)
        : null;
}