diff --git a/src/libs/languageserverprotocol/semantictokens.cpp b/src/libs/languageserverprotocol/semantictokens.cpp
index fc8233b1704..2182aa466dd 100644
--- a/src/libs/languageserverprotocol/semantictokens.cpp
+++ b/src/libs/languageserverprotocol/semantictokens.cpp
@@ -80,8 +80,11 @@ static int convertModifiers(int modifiersData, const QList<int> &tokenModifiers)
 {
     int result = 0;
     for (int i = 0; i < tokenModifiers.size() && modifiersData > 0; ++i) {
-        if (modifiersData & 0x1)
-            result |= tokenModifiers[i];
+        if (modifiersData & 0x1) {
+            const int modifier = tokenModifiers[i];
+            if (modifier > 0)
+                result |= modifier;
+        }
         modifiersData = modifiersData >> 1;
     }
     return result;
diff --git a/src/plugins/languageclient/semantichighlightsupport.cpp b/src/plugins/languageclient/semantichighlightsupport.cpp
index 2038f91f18c..9d442ca7ce5 100644
--- a/src/plugins/languageclient/semantichighlightsupport.cpp
+++ b/src/plugins/languageclient/semantichighlightsupport.cpp
@@ -254,7 +254,9 @@ void addModifiers(int key,
     if (tokenModifiers.isEmpty())
         return;
     int modifier = tokenModifiers.takeLast();
-    auto addModifier = [&](TextStyle style){
+    if (modifier < 0)
+        return;
+    auto addModifier = [&](TextStyle style) {
         if (key & modifier) // already there don't add twice
             return;
         key = key | modifier;