diff --git a/src/plugins/texteditor/semantichighlighter.cpp b/src/plugins/texteditor/semantichighlighter.cpp
index 31033815604..fa388ac40e0 100644
--- a/src/plugins/texteditor/semantichighlighter.cpp
+++ b/src/plugins/texteditor/semantichighlighter.cpp
@@ -136,7 +136,7 @@ void SemanticHighlighter::clearExtraAdditionalFormatsUntilEnd(
     QTextDocument *doc = highlighter->document();
 
     const int firstBlockToClear = lastBlockNumber + 1;
-    if (firstBlockToClear <= doc->blockCount())
+    if (firstBlockToClear >= doc->blockCount())
         return;
 
     QTextBlock b = doc->findBlockByNumber(firstBlockToClear);