diff --git a/_config.yml b/_config.yml
index 5084a22b..49b645c5 100644
--- a/_config.yml
+++ b/_config.yml
@@ -56,7 +56,7 @@ include:
   - assets/js/main.min.js
   # Only lunr is not included now to main.min.js
   - assets/js/lunr
-  # site.data.links input
+  # Input of site.data.links
   - _data/links/
 exclude:
   - .reftime
@@ -178,9 +178,11 @@ search_from_masthead: true
 
 search_provider: lunr
 lunr:
-  # No we have all the valuable content in collections
+  # No we have all the valuable content in collections (collection.docs) 
+  # that lunr indexes by default if search: true
   # Standalone pages like, sitemap.xml, 404, etc. should not be searched
   search_within_pages: false
+  test_text_1: "abrakadabra"
 
 # search_provider: algolia
 # algolia:
diff --git a/doc/_doc-guide/02_Tools/01_Self_made_tools/01_Tests/README.md b/doc/_doc-guide/02_Tools/01_Self_made_tools/01_Tests/README.md
index 6bffc87e..5511ac8b 100644
--- a/doc/_doc-guide/02_Tools/01_Self_made_tools/01_Tests/README.md
+++ b/doc/_doc-guide/02_Tools/01_Self_made_tools/01_Tests/README.md
@@ -61,6 +61,10 @@ options {
 };
 ```
 
+## Tests of custom markdown in header [[source]] and [[with turumturum id|doc-jekyll-extensions#titleid-markdown-extension]]
+
+## Tests of liquid expression {{ site.lunr.test_text_1 }} in header of {{ site.title }}
+
 ---------------------
 
 Introduction to {{ site.product.short_name }} is a test for pages without description/subtitle, but text part between the title and the first heading which can have tooltips too this way.