This database has information for all major versions from WP 1.2.1 through 5.1.
|4.9||wp-includes/user.php||1339||View in context||filter|
|5.0||wp-includes/user.php||1343||View in context||filter|
|5.1||wp-includes/user.php||1418||View in context||filter|
We find related hooks using word stems. username_exists has 2 significant word stem(s):
exists. Note that some of the hooks below may not appear in all versions of WP.