Theme_My_Login_Extension::activate()

public function activate() {
    /**
     * Fires when an extension is being activated.
     *
     * @since 7.0.14
     *
     * @param string $name The extension name.
     */
    do_action( 'tml_activate_extension', $this->get_name() );

    $slug = $this->get_slug();

    /**
     * Fires when the extension is being activated.
     *
     * The dynamic portion of the hook name, `$slug`, refers to the extension slug.
     *
     * @since 7.0
     */
    do_action( "tml_activate_{$slug}" );
}

View src/includes/class-theme-my-login-extension.php, line 401 on GitHub