diff --git a/docs/mkdocs/docs/api/basic_json/json_base_class_t.md b/docs/mkdocs/docs/api/basic_json/json_base_class_t.md
index 3318cd211..a3f317cd0 100644
--- a/docs/mkdocs/docs/api/basic_json/json_base_class_t.md
+++ b/docs/mkdocs/docs/api/basic_json/json_base_class_t.md
@@ -41,4 +41,4 @@ The type `CustomBaseClass` has to be a default-constructible class.
 
 ## Version history
 
-- Added in version ?.?.?.
+- Added in version 3.12.0.