Try prevent a crash

addons/lspclient/lspclientpluginview.cpp

@@ -2281,7 +2281,11 @@ public:
                             this,
                             SLOT(clearSemanticTokensHighlighting(KTextEditor::Document *)),
                             Qt::UniqueConnection);
-
+                    connect(doc,
+                            SIGNAL(aboutToClose(KTextEditor::Document *)),
+                            this,
+                            SLOT(clearSemanticTokensHighlighting(KTextEditor::Document *)),
+                            Qt::UniqueConnection);
                     doSemanticHighlighting(activeView);
                 }
             }

addons/lspclient/lspsemantichighlighting.cpp

@@ -17,7 +17,9 @@ void SemanticHighlighter::remove(const QUrl &url)
     auto &movingRanges = it->movingRanges;
     for (auto mr : movingRanges) {
         delete mr;
+        mr = nullptr;
     }
+    movingRanges.clear();
     m_docSemanticInfo.remove(url);
 }