diff --git a/src/part/dotgraphview.h b/src/part/dotgraphview.h
--- a/src/part/dotgraphview.h
+++ b/src/part/dotgraphview.h
@@ -83,6 +83,7 @@
 
   bool KGRAPHVIEWER_EXPORT loadDot(const QString& dotFileName);
   bool KGRAPHVIEWER_EXPORT loadLibrary(const QString& dotFileName);
+  bool KGRAPHVIEWER_EXPORT loadLibrarySync(const QString& dotFileName);
   bool loadLibrary(graph_t* graph, const QString& layoutCommand = "dot");
 
   void readViewConfig();
diff --git a/src/part/dotgraphview.cpp b/src/part/dotgraphview.cpp
--- a/src/part/dotgraphview.cpp
+++ b/src/part/dotgraphview.cpp
@@ -896,6 +896,43 @@
   return true;
 }
 
+bool DotGraphView::loadLibrarySync(const QString& dotFileName)
+{
+  qCDebug(KGRAPHVIEWERLIB_LOG) << "loading sync: '" << dotFileName << "'";
+  Q_D(DotGraphView);
+  if (d->m_canvas)
+    d->m_canvas->clear();
+  QGraphicsSimpleTextItem* loadingLabel = d->m_canvas->addSimpleText(i18n("graph %1 is getting loaded...", dotFileName));
+  loadingLabel->setZValue(100);
+  centerOn(loadingLabel);
+
+  qCDebug(KGRAPHVIEWERLIB_LOG) << dotFileName;
+  FILE* fp = fopen(dotFileName.toUtf8().data(), "r");
+  if (!fp) {
+      qCWarning(KGRAPHVIEWERLIB_LOG) << "Failed to open file " << dotFileName;
+      return false;
+  }
+  graph_t* graph = agread(fp, nullptr);
+  if (!graph) {
+      qCWarning(KGRAPHVIEWERLIB_LOG) << "Failed to read file, retrying to work around graphviz bug(?)";
+      rewind(fp);
+     graph = agread(fp, nullptr);
+  }
+  fclose(fp);
+  if (!graph) {
+      qCWarning(KGRAPHVIEWERLIB_LOG) << "Failed to read file " << dotFileName;
+      return false;
+  }
+
+  QString layoutCommand = (d->m_graph ? d->m_graph->layoutCommand() : QString());
+  if (layoutCommand.isEmpty()) {
+      layoutCommand = d->m_graph ? d->m_graph->chooseLayoutProgramForFile(dotFileName) : "dot";
+  }
+  d->m_layoutThread.layoutGraph(graph, layoutCommand);
+
+  return true;
+}
+
 bool DotGraphView::loadLibrary(const QString& dotFileName)
 {
   qCDebug(KGRAPHVIEWERLIB_LOG) << "'" << dotFileName << "'";
diff --git a/src/part/kgraphviewer_part.cpp b/src/part/kgraphviewer_part.cpp
--- a/src/part/kgraphviewer_part.cpp
+++ b/src/part/kgraphviewer_part.cpp
@@ -192,7 +192,8 @@
         return false;
       break;
     case InternalLibrary:
-      if (!d->m_widget->loadLibrary(localFilePath()))
+      // kpart expects loading to be done sync in this method
+      if (!d->m_widget->loadLibrarySync(localFilePath()))
         return false;
       break;
     default:
diff --git a/src/part/loadagraphthread.cpp b/src/part/loadagraphthread.cpp
--- a/src/part/loadagraphthread.cpp
+++ b/src/part/loadagraphthread.cpp
@@ -47,6 +47,17 @@
 
 void LoadAGraphThread::loadFile(const QString& dotFileName)
 {
+  // FIXME: deadlock possible
+  // if thread is still running or queued finished signal of the thread has not
+  // yet been delivered so its handler who would release the semaphore,
+  // then the semaphore can not be acquired and this will block the (main) thread
+  // which called LoadAGraphThread::loadFile().
+  // That one though very much might have also been the one which before invoked this
+  // method and thus the still running thread or yet-to-be delivered finished signal.
+  // But being blocked now, it will not reach its event loop where the queued finished
+  // signal of the thread would be processed and delivered, so in the further processing
+  // by the signal handler this semaphore would be released
+  // -> blocked ourselves without any escape
   sem.acquire();
   m_dotFileName = dotFileName;
   m_g = nullptr;