The username isn't a thing in v3.

jesseleite · jesseleite · commit 06cad438fd8c · 2020-02-28T16:30:50.000-05:00
diff --git a/src/Auth/UserTags.php b/src/Auth/UserTags.php
@@ -53,13 +53,6 @@ public function index()
             }
         }
 
-        // Get a user by username, if the `username` parameter was used.
-        if ($username = $this->get('username')) {
-            if (! $user = User::whereUsername($username)) {
-                return $this->parseNoResults();
-            }
-        }
-
         // Get a user by email, if the `email` parameter was used.
         if ($email = $this->get('email')) {
             if (! $user = User::whereEmail($email)) {

Original file line number	Diff line number	Diff line change
`@@ -53,13 +53,6 @@ public function index()`
`53`	`53`	`}`
`54`	`54`	`}`
`55`	`55`
`56`		- // Get a user by username, if the `username` parameter was used.
`57`		`- if ($username = $this->get('username')) {`
`58`		`- if (! $user = User::whereUsername($username)) {`
`59`		`- return $this->parseNoResults();`
`60`		`- }`
`61`		`- }`
`62`		`-`
`63`	`56`	// Get a user by email, if the `email` parameter was used.
`64`	`57`	`if ($email = $this->get('email')) {`
`65`	`58`	`if (! $user = User::whereEmail($email)) {`