Show license dialog after legacy activation

Allows the user to directly renew the just activated legacy license

config/areas/system/dialogs.php

@@ -8,7 +8,7 @@
 return [
 	// license key
 	'license' => [
-		'load' => function () {
+		'load' => $licenseDialog = function () {
 			$kirby      = App::instance();
 			$license    = $kirby->system()->license();
 			$obfuscated = $kirby->user()->isAdmin() === false;
@@ -95,14 +95,18 @@
 				]
 			];
 		},
-		'submit' => function () {
+		'submit' => function () use ($licenseDialog) {
 			// @codeCoverageIgnoreStart
 			$kirby = App::instance();
 			$kirby->system()->register(
 				$kirby->request()->get('license'),
 				$kirby->request()->get('email')
 			);
 
+			if ($kirby->system()->license()->isLegacy() === true) {
+				return $licenseDialog();
+			}
+
 			return [
 				'event'   => 'system.register',
 				'message' => I18n::translate('license.success')