diff --git a/topics/reference_guide/api_notable/api_notable_list_2021.md b/topics/reference_guide/api_notable/api_notable_list_2021.md
index 95aac6be1..4a6544ab6 100644
--- a/topics/reference_guide/api_notable/api_notable_list_2021.md
+++ b/topics/reference_guide/api_notable/api_notable_list_2021.md
@@ -4,4 +4,7 @@
 
 ## 2021.1
 
-### Notable Changes in IntelliJ Platform 2021.1
\ No newline at end of file
+### Notable Changes in IntelliJ Platform 2021.1
+
+_Add unambiguous imports on the fly_ for custom languages
+: Override [`ReferenceImporter#isAddUnambiguousImportsOnTheFlyEnabled()`](upsource:///platform/analysis-impl/src/com/intellij/codeInsight/daemon/ReferenceImporter.java) and provide corresponding user setting. Implement `HintAction` with `fixSilently()` and hook it up to highlighting as a quick fix for unresolved reference.
\ No newline at end of file