diff --git a/ui/qt/conversation_hash_tables_dialog.cpp b/ui/qt/conversation_hash_tables_dialog.cpp
index 86cb89073b..11b6cbbf0c 100644
--- a/ui/qt/conversation_hash_tables_dialog.cpp
+++ b/ui/qt/conversation_hash_tables_dialog.cpp
@@ -38,7 +38,7 @@ ConversationHashTablesDialog::ConversationHashTablesDialog(QWidget *parent) :
 {
     ui->setupUi(this);
     if (parent) loadGeometry(parent->width() * 3 / 4, parent->height() * 3 / 4);
-
+    setAttribute(Qt::WA_DeleteOnClose, true);
     setWindowTitle(wsApp->windowTitleString(tr("Dissector Tables")));
 
     QString html;
diff --git a/ui/qt/display_filter_expression_dialog.cpp b/ui/qt/display_filter_expression_dialog.cpp
index c63aba0432..cb0d75bfa5 100644
--- a/ui/qt/display_filter_expression_dialog.cpp
+++ b/ui/qt/display_filter_expression_dialog.cpp
@@ -71,6 +71,7 @@ DisplayFilterExpressionDialog::DisplayFilterExpressionDialog(QWidget *parent) :
 {
     ui->setupUi(this);
     if (parent) loadGeometry(parent->width() * 2 / 3, parent->height());
+    setAttribute(Qt::WA_DeleteOnClose, true);
 
     setWindowTitle(wsApp->windowTitleString(tr("Display Filter Expression")));
     setWindowIcon(wsApp->normalIcon());
diff --git a/ui/qt/dissector_tables_dialog.cpp b/ui/qt/dissector_tables_dialog.cpp
index 07483bb113..7a1490b21b 100644
--- a/ui/qt/dissector_tables_dialog.cpp
+++ b/ui/qt/dissector_tables_dialog.cpp
@@ -83,7 +83,7 @@ DissectorTablesDialog::DissectorTablesDialog(QWidget *parent) :
 {
     ui->setupUi(this);
     if (parent) loadGeometry(parent->width() * 3 / 4, parent->height() * 3 / 4);
-
+    setAttribute(Qt::WA_DeleteOnClose, true);
     setWindowTitle(wsApp->windowTitleString(tr("Dissector Tables")));
 
     on_tableTreeWidget_itemSelectionChanged();
diff --git a/ui/qt/main_window.cpp b/ui/qt/main_window.cpp
index eeab9fa92f..380ef7e357 100644
--- a/ui/qt/main_window.cpp
+++ b/ui/qt/main_window.cpp
@@ -66,6 +66,7 @@ DIAG_ON(frame-larger-than=)
 #include <ui/qt/widgets/display_filter_edit.h>
 #include "export_dissection_dialog.h"
 #include "file_set_dialog.h"
+#include "filter_dialog.h"
 #include "funnel_statistics.h"
 #include "import_text_dialog.h"
 #include "interface_toolbar.h"
@@ -271,6 +272,8 @@ MainWindow::MainWindow(QWidget *parent) :
     , capture_interfaces_dialog_(NULL)
     , info_data_()
 #endif
+    , display_filter_dlg_(NULL)
+    , capture_filter_dlg_(NULL)
 #ifdef _WIN32
     , pipe_timer_(NULL)
 #else
@@ -739,12 +742,18 @@ MainWindow::~MainWindow()
     disconnect(main_ui_->mainStack, 0, 0, 0);
 
 #ifndef Q_OS_MAC
-    // file_set_dialog_ is a subclass of GeometryStateDialog.
+    // Below dialogs inherit GeometryStateDialog
     // For reasons described in geometry_state_dialog.h no parent is set when
-    // instantiating the dialog and as a result the object is not automatically
-    // freed by its parent. Free it here explicitly to avoid leak and numerous
+    // instantiating the dialogs and as a resul objects are not automatically
+    // freed by its parent. Free then here explicitly to avoid leak and numerous
     // Valgrind complaints.
     delete file_set_dialog_;
+    delete capture_filter_dlg_;
+    delete display_filter_dlg_;
+#ifdef HAVE_LIBPCAP
+    delete capture_interfaces_dialog_;
+#endif
+
 #endif
     delete main_ui_;
 }
diff --git a/ui/qt/main_window.h b/ui/qt/main_window.h
index 9eeacd0f1a..2208be7fe5 100644
--- a/ui/qt/main_window.h
+++ b/ui/qt/main_window.h
@@ -63,6 +63,7 @@ class AccordionFrame;
 class ByteViewTab;
 class CaptureInterfacesDialog;
 class FileSetDialog;
+class FilterDialog;
 class FunnelStatistics;
 class MainWelcome;
 class PacketList;
@@ -179,6 +180,8 @@ private:
     CaptureInterfacesDialog *capture_interfaces_dialog_;
     info_data_t info_data_;
 #endif
+    FilterDialog *display_filter_dlg_;
+    FilterDialog *capture_filter_dlg_;
 
     // Pipe input
     gint                pipe_source_;
diff --git a/ui/qt/main_window_slots.cpp b/ui/qt/main_window_slots.cpp
index 59e6d2ebbf..ff0c3e4163 100644
--- a/ui/qt/main_window_slots.cpp
+++ b/ui/qt/main_window_slots.cpp
@@ -2728,7 +2728,6 @@ void MainWindow::matchFieldFilter(FilterAction::Action action, FilterAction::Act
     emit filterAction(field_filter, action, filter_type);
 }
 
-static FilterDialog *display_filter_dlg_ = NULL;
 void MainWindow::on_actionAnalyzeDisplayFilters_triggered()
 {
     if (!display_filter_dlg_) {
@@ -3736,7 +3735,6 @@ void MainWindow::on_actionCaptureRestart_triggered()
     startCapture();
 }
 
-static FilterDialog *capture_filter_dlg_ = NULL;
 void MainWindow::on_actionCaptureCaptureFilters_triggered()
 {
     if (!capture_filter_dlg_) {
diff --git a/ui/qt/manage_interfaces_dialog.cpp b/ui/qt/manage_interfaces_dialog.cpp
index 55948bf167..b124f46302 100644
--- a/ui/qt/manage_interfaces_dialog.cpp
+++ b/ui/qt/manage_interfaces_dialog.cpp
@@ -87,6 +87,7 @@ ManageInterfacesDialog::ManageInterfacesDialog(QWidget *parent) :
 {
     ui->setupUi(this);
     loadGeometry();
+    setAttribute(Qt::WA_DeleteOnClose, true);
 
 #ifdef Q_OS_MAC
     ui->addPipe->setAttribute(Qt::WA_MacSmallSize, true);
diff --git a/ui/qt/supported_protocols_dialog.cpp b/ui/qt/supported_protocols_dialog.cpp
index 0d9c582124..a49a89c7b1 100644
--- a/ui/qt/supported_protocols_dialog.cpp
+++ b/ui/qt/supported_protocols_dialog.cpp
@@ -53,6 +53,7 @@ SupportedProtocolsDialog::SupportedProtocolsDialog(QWidget *parent) :
 {
     ui->setupUi(this);
     if (parent) loadGeometry(parent->width() * 3 / 4, parent->height());
+    setAttribute(Qt::WA_DeleteOnClose, true);
     setWindowTitle(wsApp->windowTitleString(tr("Supported Protocols")));
 
     // Some of our names are unreasonably long.