diff -u b/core/modules/views/config/schema/views.filter.schema.yml b/core/modules/views/config/schema/views.filter.schema.yml
--- b/core/modules/views/config/schema/views.filter.schema.yml
+++ b/core/modules/views/config/schema/views.filter.schema.yml
@@ -98,6 +98,7 @@
   label: 'Filter value'
 
 views.filter_value.equality:
+  type: string
   label: 'Equality'
 
 views.filter.many_to_one: