Andrei Mateescu · catch
--- a/core/modules/system/system.install
+++ b/core/modules/system/system.install
+*/
+function system_update_11201(): void {
+ $schema = \Drupal::database()->schema();
+
+ if ($schema->tableExists('router') && !$schema->fieldExists('router', 'alias')) {
+   $spec = [
+     'fields' => [
+       'alias' => [
+         'description' => 'The alias of the route, if applicable.',
+         'type' => 'varchar_ascii',
+         'length' => 255,
+       ],
+     ],
+   ];
+   $schema->addField('router', 'alias', $spec['fields']['alias']);
+   $schema->addIndex('router', 'alias', ['alias'], $spec);