Index: sidebar/bookmarks_module/bookmarks_module.h
===================================================================
--- sidebar/bookmarks_module/bookmarks_module.h
+++ sidebar/bookmarks_module/bookmarks_module.h
@@ -28,6 +28,7 @@
 
 #include <QDebug>
 
+class QStandardItemModel;
 
 class KonqSideBarBookmarksModule : public KonqSidebarModule
 {
Index: sidebar/tree_module/tree_module.h
===================================================================
--- sidebar/tree_module/tree_module.h
+++ sidebar/tree_module/tree_module.h
@@ -37,10 +37,6 @@
 
 #include <kio_version.h>
 
-#define KDIRMODEL_HAS_ROOT_NODE  KIO_VERSION >= QT_VERSION_CHECK(5, 66, 0) // set to the appropriate check here
-#define KDIRMODEL_HAS_ROOT_NODE 1
-
-
 
 class KonqSideBarTreeModule : public KonqSidebarModule
 {
Index: sidebar/tree_module/tree_module.cpp
===================================================================
--- sidebar/tree_module/tree_module.cpp
+++ sidebar/tree_module/tree_module.cpp
@@ -62,24 +62,13 @@
     sorted_model->setSourceModel(model); 
     model->dirLister()->setDirOnlyMode(true);
 
-#if KDIRMODEL_HAS_ROOT_NODE
-    if (m_initURL.isLocalFile()) { // .scheme() == "file"
-        model->openUrl(m_initURL, KDirModel::ShowRoot);
-    } else {
-        model->dirLister()->openUrl(m_initURL, KDirLister::Keep);
-    }
-#else
-    model->dirLister()->openUrl(m_initURL, KDirLister::Keep);
-#endif
+    model->openUrl(m_initURL, KDirModel::ShowRoot);
 
     treeView->setModel(sorted_model);
 
-    treeView->setColumnHidden(1, true);
-    treeView->setColumnHidden(2, true);
-    treeView->setColumnHidden(3, true);
-    treeView->setColumnHidden(4, true);
-    treeView->setColumnHidden(5, true);
-    treeView->setColumnHidden(6, true);
+    for (int i = 1; i <= 6; i++) {
+        treeView->setColumnHidden(i, true);
+    }
 
     model->expandToUrl(m_initURL); // KDir is async, we'll just have to wait for slotKDirCompleted()
     connect(model, &KDirModel::expand,
@@ -114,9 +103,9 @@
     if (url.isRelative()) {
         url.setScheme("file");
         if (url.path() == "~") {
-            QString homePath = QDir::homePath();
+            const QString homePath = QDir::homePath();
             if (!homePath.endsWith("/")) {
-                url.setPath(homePath.append("/"));
+                url.setPath(homePath + "/");
             } else {
                 url.setPath(homePath);
             }
@@ -154,11 +143,7 @@
 
     m_lastURL = target_url;
 
-#if KDIRMODEL_HAS_ROOT_NODE
     if (!index.isValid() && target_url.scheme() == m_initURL.scheme()) {
-#else
-    if (!index.isValid() && target_url.scheme() == m_initURL.scheme() && target_url != QUrl::fromLocalFile("/")) {
-#endif
         if (do_openURLreq) {
             connect(model, &KDirModel::expand,
                 this,  &KonqSideBarTreeModule::slotKDirExpand_setSelection   );