diff --git a/src/plugins/help/CMakeLists.txt b/src/plugins/help/CMakeLists.txt
index a6711862638..4d5fd23283e 100644
--- a/src/plugins/help/CMakeLists.txt
+++ b/src/plugins/help/CMakeLists.txt
@@ -26,6 +26,11 @@ add_qtc_plugin(Help
     xbelsupport.cpp xbelsupport.h
 )
 
+extend_qtc_plugin(Help
+  CONDITION Qt5_VERSION VERSION_GREATER_EQUAL 5.15.0
+  DEFINES HELP_NEW_FILTER_ENGINE
+)
+
 extend_qtc_plugin(Help
   CONDITION FWWebKit AND FWAppKit
   FEATURE_INFO "Native WebKit help viewer"