diff --git a/resources/skins/dark/metadata.xml b/resources/skins/dark/metadata.xml
index db3f2ab4e..db8622652 100755
--- a/resources/skins/dark/metadata.xml
+++ b/resources/skins/dark/metadata.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<skin version="0.04">
+<skin version="0.05">
   <author>
     <name>Martin Rotter</name>
     <email>rotter.martinos@gmail.com</email>
@@ -7,5 +7,6 @@
   <palette>
     <color key="1">#7ae2ff</color>
     <color key="2">#f08f84</color>
+    <color key="3">#77dd77</color>
   </palette>
 </skin>
\ No newline at end of file
diff --git a/resources/skins/vergilius/metadata.xml b/resources/skins/vergilius/metadata.xml
index caefe5f2e..9c47a6def 100755
--- a/resources/skins/vergilius/metadata.xml
+++ b/resources/skins/vergilius/metadata.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<skin version="0.23">
+<skin version="0.24">
   <author>
     <name>Martin Rotter</name>
     <email>rotter.martinos@gmail.com</email>
@@ -7,5 +7,6 @@
   <palette>
     <color key="1">#4861f0</color>
     <color key="2">#d93636</color>
+    <color key="3">#77dd77</color>
   </palette>
 </skin>
\ No newline at end of file
diff --git a/src/librssguard/core/messagesforfiltersmodel.cpp b/src/librssguard/core/messagesforfiltersmodel.cpp
new file mode 100755
index 000000000..7ebb1762a
--- /dev/null
+++ b/src/librssguard/core/messagesforfiltersmodel.cpp
@@ -0,0 +1,132 @@
+// For license of this file, see <project-root-folder>/LICENSE.md.
+
+#include "core/messagesforfiltersmodel.h"
+
+#include "core/messagefilter.h"
+#include "definitions/definitions.h"
+#include "exceptions/filteringexception.h"
+#include "miscellaneous/application.h"
+#include "miscellaneous/skinfactory.h"
+
+MessagesForFiltersModel::MessagesForFiltersModel(QObject* parent) : QAbstractTableModel(parent) {
+  m_headerData << tr("Read") << tr("Important") << tr("Title")
+               << tr("URL") << tr("Author") << tr("Created on");
+}
+
+void MessagesForFiltersModel::setMessages(const QList<Message>& messages) {
+  m_filteringDecisions.clear();
+  m_messages = messages;
+
+  emit layoutAboutToBeChanged();
+  emit layoutChanged();
+}
+
+int MessagesForFiltersModel::rowCount(const QModelIndex& parent) const {
+  Q_UNUSED(parent)
+  return m_messages.size();
+}
+
+int MessagesForFiltersModel::columnCount(const QModelIndex& parent) const {
+  Q_UNUSED(parent)
+  return m_headerData.size();
+}
+
+QVariant MessagesForFiltersModel::data(const QModelIndex& index, int role) const {
+  auto msg = messageForRow(index.row());
+
+  switch (role) {
+    case Qt::ItemDataRole::BackgroundRole: {
+      if (m_filteringDecisions.contains(index.row())) {
+        switch (m_filteringDecisions.value(index.row())) {
+          case MessageObject::FilteringAction::Accept:
+            return qApp->skins()->currentSkin().m_colorPalette[Skin::PaletteColors::Allright];
+
+          case MessageObject::FilteringAction::Ignore:
+            return qApp->skins()->currentSkin().m_colorPalette[Skin::PaletteColors::Error];
+        }
+      }
+
+      break;
+    }
+
+    case Qt::ItemDataRole::DisplayRole: {
+      switch (index.column()) {
+        case MFM_MODEL_ISREAD:
+          return msg.m_isRead;
+
+        case MFM_MODEL_ISIMPORTANT:
+          return msg.m_isImportant;
+
+        case MFM_MODEL_TITLE:
+          return msg.m_title;
+
+        case MFM_MODEL_URL:
+          return msg.m_url;
+
+        case MFM_MODEL_AUTHOR:
+          return msg.m_author;
+
+        case MFM_MODEL_CREATED:
+          return msg.m_created;
+      }
+
+      break;
+    }
+  }
+
+  return QVariant();
+}
+
+QVariant MessagesForFiltersModel::headerData(int section, Qt::Orientation orientation, int role) const {
+  Q_UNUSED(orientation)
+
+  switch (role) {
+    case Qt::ItemDataRole::DisplayRole:
+      if (section >=0 && section < m_headerData.size()) {
+        return m_headerData.at(section);
+      }
+
+      break;
+  }
+
+  return QVariant();
+}
+
+Qt::ItemFlags MessagesForFiltersModel::flags(const QModelIndex& index) const {
+  Q_UNUSED(index)
+  return Qt::ItemFlag::ItemIsEnabled | Qt::ItemFlag::ItemIsSelectable;
+}
+
+int MessagesForFiltersModel::messagesCount() const {
+  return m_messages.size();
+}
+
+void MessagesForFiltersModel::testFilter(MessageFilter* filter, QJSEngine* engine, MessageObject* msg_proxy) {
+  m_filteringDecisions.clear();
+
+  for (int i = 0; i < m_messages.size(); i++) {
+    Message* msg = messageForRow(i);
+
+    msg_proxy->setMessage(msg);
+
+    try {
+      MessageObject::FilteringAction decision = filter->filterMessage(engine);
+
+      m_filteringDecisions.insert(i, decision);
+    }
+    catch (const FilteringException& ex) {
+      throw ex;
+    }
+  }
+
+  emit layoutAboutToBeChanged();
+  emit layoutChanged();
+}
+
+Message* MessagesForFiltersModel::messageForRow(int row) {
+  return &m_messages[row];
+}
+
+Message MessagesForFiltersModel::messageForRow(int row) const {
+  return m_messages[row];
+}
diff --git a/src/librssguard/core/messagesforfiltersmodel.h b/src/librssguard/core/messagesforfiltersmodel.h
new file mode 100755
index 000000000..9945bad55
--- /dev/null
+++ b/src/librssguard/core/messagesforfiltersmodel.h
@@ -0,0 +1,44 @@
+// For license of this file, see <project-root-folder>/LICENSE.md.
+
+#ifndef MESSAGESFORFILTERSMODEL_H
+#define MESSAGESFORFILTERSMODEL_H
+
+#include <QAbstractTableModel>
+
+#include "core/messageobject.h"
+
+#include <QJSEngine>
+
+class MessageFilter;
+
+class MessagesForFiltersModel : public QAbstractTableModel {
+  Q_OBJECT
+
+  public:
+    explicit MessagesForFiltersModel(QObject* parent = nullptr);
+
+    virtual int rowCount(const QModelIndex& parent) const;
+    virtual int columnCount(const QModelIndex& parent) const;
+    virtual QVariant data(const QModelIndex& index, int role) const;
+    virtual QVariant headerData(int section, Qt::Orientation orientation, int role) const;
+    virtual Qt::ItemFlags flags(const QModelIndex& index) const;
+
+  public:
+    int messagesCount() const;
+    void testFilter(MessageFilter* filter, QJSEngine* engine, MessageObject* msg_proxy);
+
+    Message messageForRow(int row) const;
+    Message* messageForRow(int row);
+
+  public slots:
+    void setMessages(const QList<Message>& messages);
+
+  private:
+    QList<QString> m_headerData{};
+    QList<Message> m_messages{};
+
+    // Key is integer position of the message within the list of messages.
+    QMap<int, MessageObject::FilteringAction> m_filteringDecisions{};
+};
+
+#endif // MESSAGESFORFILTERSMODEL_H
diff --git a/src/librssguard/definitions/definitions.h b/src/librssguard/definitions/definitions.h
index ecd9efb47..ce386eb55 100755
--- a/src/librssguard/definitions/definitions.h
+++ b/src/librssguard/definitions/definitions.h
@@ -218,6 +218,14 @@
 #define FDS_MODEL_TITLE_INDEX           0
 #define FDS_MODEL_COUNTS_INDEX          1
 
+// Indexes of columns for message filter manager models.
+#define MFM_MODEL_ISREAD        0
+#define MFM_MODEL_ISIMPORTANT   1
+#define MFM_MODEL_TITLE         2
+#define MFM_MODEL_URL           3
+#define MFM_MODEL_AUTHOR        4
+#define MFM_MODEL_CREATED       5
+
 #if defined(Q_OS_LINUX)
 #define OS_ID   "Linux"
 #elif defined(Q_OS_OSX)
diff --git a/src/librssguard/gui/dialogs/formmessagefiltersmanager.cpp b/src/librssguard/gui/dialogs/formmessagefiltersmanager.cpp
index 18cbf1bb4..85c869e2e 100644
--- a/src/librssguard/gui/dialogs/formmessagefiltersmanager.cpp
+++ b/src/librssguard/gui/dialogs/formmessagefiltersmanager.cpp
@@ -1,12 +1,13 @@
+// For license of this file, see <project-root-folder>/LICENSE.md.
+
 #include <QDateTime>
 #include <QJSEngine>
 #include <QProcess>
 
-// For license of this file, see <project-root-folder>/LICENSE.md.
-
 #include "gui/dialogs/formmessagefiltersmanager.h"
 
 #include "core/messagefilter.h"
+#include "core/messagesforfiltersmodel.h"
 #include "exceptions/filteringexception.h"
 #include "gui/guiutilities.h"
 #include "gui/messagebox.h"
@@ -19,9 +20,15 @@
 
 FormMessageFiltersManager::FormMessageFiltersManager(FeedReader* reader, const QList<ServiceRoot*>& accounts, QWidget* parent)
   : QDialog(parent), m_feedsModel(new AccountCheckSortedModel(this)), m_rootItem(new RootItem()),
-  m_accounts(accounts), m_reader(reader), m_loadingFilter(false) {
+  m_accounts(accounts), m_reader(reader), m_loadingFilter(false), m_msgModel(new MessagesForFiltersModel(this)) {
   m_ui.setupUi(this);
 
+  std::sort(m_accounts.begin(), m_accounts.end(), [](const ServiceRoot* lhs, const ServiceRoot* rhs) {
+    return lhs->title().compare(rhs->title(), Qt::CaseSensitivity::CaseInsensitive) < 0;
+  });
+
+  m_ui.m_treeExistingMessages->setModel(m_msgModel);
+
   GuiUtilities::applyDialogProperties(*this, qApp->icons()->fromTheme(QSL("view-list-details")));
 
   m_ui.m_treeFeeds->setIndentation(FEEDS_VIEW_INDENTATION);
@@ -32,9 +39,17 @@ FormMessageFiltersManager::FormMessageFiltersManager(FeedReader* reader, const Q
   m_ui.m_btnRemoveSelected->setIcon(qApp->icons()->fromTheme(QSL("list-remove")));
   m_ui.m_btnBeautify->setIcon(qApp->icons()->fromTheme(QSL("format-justify-fill")));
   m_ui.m_btnTest->setIcon(qApp->icons()->fromTheme(QSL("media-playback-start")));
+  m_ui.m_btnRunOnMessages->setIcon(qApp->icons()->fromTheme(QSL("media-playback-start")));
   m_ui.m_btnDetailedHelp->setIcon(qApp->icons()->fromTheme(QSL("help-contents")));
   m_ui.m_txtScript->setFont(QFontDatabase::systemFont(QFontDatabase::SystemFont::FixedFont));
 
+  m_ui.m_treeExistingMessages->header()->setSectionResizeMode(MFM_MODEL_ISREAD, QHeaderView::ResizeMode::ResizeToContents);
+  m_ui.m_treeExistingMessages->header()->setSectionResizeMode(MFM_MODEL_ISIMPORTANT, QHeaderView::ResizeMode::ResizeToContents);
+  m_ui.m_treeExistingMessages->header()->setSectionResizeMode(MFM_MODEL_AUTHOR, QHeaderView::ResizeMode::ResizeToContents);
+  m_ui.m_treeExistingMessages->header()->setSectionResizeMode(MFM_MODEL_CREATED, QHeaderView::ResizeMode::ResizeToContents);
+  m_ui.m_treeExistingMessages->header()->setSectionResizeMode(MFM_MODEL_TITLE, QHeaderView::ResizeMode::Interactive);
+  m_ui.m_treeExistingMessages->header()->setSectionResizeMode(MFM_MODEL_URL, QHeaderView::ResizeMode::Interactive);
+
   connect(m_ui.m_btnDetailedHelp, &QPushButton::clicked, this, []() {
     qApp->web()->openUrlInExternalBrowser(MSG_FILTERING_HELP);
   });
@@ -55,6 +70,8 @@ FormMessageFiltersManager::FormMessageFiltersManager(FeedReader* reader, const Q
   connect(m_ui.m_btnUncheckAll, &QPushButton::clicked, m_feedsModel->sourceModel(), &AccountCheckModel::uncheckAllItems);
   connect(m_feedsModel->sourceModel(), &AccountCheckModel::checkStateChanged,
           this, &FormMessageFiltersManager::onFeedChecked);
+  connect(m_ui.m_treeFeeds->selectionModel(), &QItemSelectionModel::selectionChanged,
+          this, &FormMessageFiltersManager::displayMessagesOfFeed);
 
   initializeTestingMessage();
   loadFilters();
@@ -104,7 +121,7 @@ void FormMessageFiltersManager::addNewFilter() {
   try {
     auto* fltr = m_reader->addMessageFilter(
       tr("New message filter"),
-      QSL("function filterMessage() { return 1; }"));
+      QSL("function filterMessage() { return MessageObject.Accept; }"));
     auto* it = new QListWidgetItem(fltr->name(), m_ui.m_listFilters);
 
     it->setData(Qt::ItemDataRole::UserRole, QVariant::fromValue<MessageFilter*>(fltr));
@@ -145,6 +162,8 @@ void FormMessageFiltersManager::loadFilter() {
 }
 
 void FormMessageFiltersManager::testFilter() {
+  m_ui.m_txtErrors->clear();
+
   // Perform per-message filtering.
   QJSEngine filter_engine;
   QSqlDatabase database = qApp->database()->connection(metaObject()->className());
@@ -155,10 +174,24 @@ void FormMessageFiltersManager::testFilter() {
                                              : NO_PARENT_CATEGORY,
                         {});
   auto* fltr = selectedFilter();
-  Message msg = testingMessage();
 
   MessageFilter::initializeFilteringEngine(filter_engine, &msg_obj);
 
+  // Test real messages.
+  try {
+    m_msgModel->testFilter(fltr, &filter_engine, &msg_obj);
+  }
+  catch (const FilteringException& ex) {
+    m_ui.m_txtErrors->setTextColor(Qt::GlobalColor::red);
+    m_ui.m_txtErrors->insertPlainText(tr("EXISTING messages filtering error: '%1'.\n").arg(ex.message()));
+
+    // See output.
+    m_ui.m_twMessages->setCurrentIndex(2);
+  }
+
+  // Test sample message.
+  Message msg = testingMessage();
+
   msg_obj.setMessage(&msg);
 
   try {
@@ -182,19 +215,37 @@ void FormMessageFiltersManager::testFilter() {
                                           QString::number(msg.m_created.toMSecsSinceEpoch()),
                                           msg.m_contents);
 
-    m_ui.m_txtErrors->setPlainText(answer);
+    m_ui.m_txtErrors->insertPlainText(answer);
   }
   catch (const FilteringException& ex) {
     m_ui.m_txtErrors->setTextColor(Qt::GlobalColor::red);
-    m_ui.m_txtErrors->setPlainText(tr("JavaScript-based filter contains errors: '%1'.").arg(ex.message()));
-  }
+    m_ui.m_txtErrors->insertPlainText(tr("SAMPLE message filtering error: '%1'.\n").arg(ex.message()));
 
-  // See output.
-  m_ui.m_tcMessage->setCurrentIndex(1);
+    // See output.
+    m_ui.m_twMessages->setCurrentIndex(2);
+  }
+}
+
+void FormMessageFiltersManager::displayMessagesOfFeed() {
+  auto* item = m_feedsModel->sourceModel()->itemForIndex(m_feedsModel->mapToSource(m_ui.m_treeFeeds->currentIndex()));
+
+  if (item != nullptr) {
+    m_msgModel->setMessages(item->undeletedMessages());
+  }
+  else {
+    m_msgModel->setMessages({});
+  }
 }
 
 void FormMessageFiltersManager::loadAccount(ServiceRoot* account) {
   m_feedsModel->setRootItem(account, false, true);
+
+  if (account != nullptr) {
+    m_msgModel->setMessages(account->undeletedMessages());
+  }
+  else {
+    m_msgModel->setMessages({});
+  }
 }
 
 void FormMessageFiltersManager::loadFilterFeedAssignments(MessageFilter* filter, ServiceRoot* account) {
@@ -233,6 +284,7 @@ void FormMessageFiltersManager::onFeedChecked(RootItem* item, Qt::CheckState sta
     return;
   }
 
+  // Update feed/filter assignemnts.
   switch (state) {
     case Qt::CheckState::Checked:
       m_reader->assignMessageFilterToFeed(feed, selectedFilter());
@@ -272,7 +324,7 @@ void FormMessageFiltersManager::showFilter(MessageFilter* filter) {
   }
 
   // See message.
-  m_ui.m_tcMessage->setCurrentIndex(0);
+  m_ui.m_twMessages->setCurrentIndex(0);
   m_loadingFilter = false;
 }
 
@@ -298,7 +350,7 @@ void FormMessageFiltersManager::beautifyScript() {
   proc_clang_format.setProgram(QSL("clang-format"));
 #endif
 
-  if (!proc_clang_format.open()) {
+  if (!proc_clang_format.open() || proc_clang_format.error() == QProcess::ProcessError::FailedToStart) {
     MessageBox::show(this, QMessageBox::Icon::Critical,
                      tr("Cannot find 'clang-format'"),
                      tr("Script was not beautified, because 'clang-format' tool was not found."));
diff --git a/src/librssguard/gui/dialogs/formmessagefiltersmanager.h b/src/librssguard/gui/dialogs/formmessagefiltersmanager.h
index a2ca53646..e97e6bce3 100644
--- a/src/librssguard/gui/dialogs/formmessagefiltersmanager.h
+++ b/src/librssguard/gui/dialogs/formmessagefiltersmanager.h
@@ -12,6 +12,7 @@
 class AccountCheckSortedModel;
 class MessageFilter;
 class FeedReader;
+class MessagesForFiltersModel;
 
 class FormMessageFiltersManager : public QDialog {
   Q_OBJECT
@@ -30,6 +31,7 @@ class FormMessageFiltersManager : public QDialog {
     void loadFilter();
     void loadFilters();
     void testFilter();
+    void displayMessagesOfFeed();
 
     // Load feeds/categories tree.
     void loadAccount(ServiceRoot* account);
@@ -56,6 +58,7 @@ class FormMessageFiltersManager : public QDialog {
     QList<ServiceRoot*> m_accounts;
     FeedReader* m_reader;
     bool m_loadingFilter;
+    MessagesForFiltersModel* m_msgModel;
 };
 
 #endif // FORMMESSAGEFILTERSMANAGER_H
diff --git a/src/librssguard/gui/dialogs/formmessagefiltersmanager.ui b/src/librssguard/gui/dialogs/formmessagefiltersmanager.ui
index 816e54d1f..40b0bfaa7 100644
--- a/src/librssguard/gui/dialogs/formmessagefiltersmanager.ui
+++ b/src/librssguard/gui/dialogs/formmessagefiltersmanager.ui
@@ -6,386 +6,407 @@
    <rect>
     <x>0</x>
     <y>0</y>
-    <width>845</width>
-    <height>644</height>
+    <width>1229</width>
+    <height>546</height>
    </rect>
   </property>
   <property name="windowTitle">
    <string>Message filters</string>
   </property>
-  <layout class="QGridLayout" name="gridLayout_2">
-   <item row="0" column="0">
-    <layout class="QGridLayout" name="gridLayout">
-     <item row="1" column="2">
-      <widget class="QPushButton" name="m_btnRemoveSelected">
-       <property name="text">
-        <string>Remove selected</string>
-       </property>
-      </widget>
-     </item>
-     <item row="1" column="1">
-      <widget class="QPushButton" name="m_btnAddNew">
-       <property name="text">
-        <string>Add new</string>
-       </property>
-      </widget>
-     </item>
-     <item row="1" column="0">
-      <spacer name="horizontalSpacer">
-       <property name="orientation">
-        <enum>Qt::Horizontal</enum>
-       </property>
-       <property name="sizeHint" stdset="0">
-        <size>
-         <width>40</width>
-         <height>20</height>
-        </size>
-       </property>
-      </spacer>
-     </item>
-     <item row="0" column="0" colspan="3">
-      <widget class="QListWidget" name="m_listFilters">
-       <property name="uniformItemSizes">
-        <bool>true</bool>
-       </property>
-      </widget>
-     </item>
-    </layout>
-   </item>
-   <item row="0" column="1">
-    <layout class="QFormLayout" name="formLayout_3">
-     <item row="0" column="0">
-      <widget class="QLabel" name="label_9">
-       <property name="text">
-        <string>Account</string>
-       </property>
-       <property name="buddy">
-        <cstring>m_cmbAccounts</cstring>
-       </property>
-      </widget>
-     </item>
-     <item row="0" column="1">
-      <widget class="QComboBox" name="m_cmbAccounts"/>
-     </item>
-     <item row="1" column="0" colspan="2">
-      <layout class="QHBoxLayout" name="horizontalLayout_5">
-       <item>
-        <widget class="QTreeView" name="m_treeFeeds">
-         <property name="minimumSize">
-          <size>
-           <width>0</width>
-           <height>150</height>
-          </size>
-         </property>
-         <property name="uniformRowHeights">
-          <bool>true</bool>
-         </property>
-         <attribute name="headerVisible">
-          <bool>false</bool>
-         </attribute>
-        </widget>
-       </item>
-       <item>
-        <layout class="QVBoxLayout" name="verticalLayout">
-         <item>
+  <layout class="QVBoxLayout" name="verticalLayout">
+   <item>
+    <widget class="QSplitter" name="splitter">
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+     <property name="handleWidth">
+      <number>1</number>
+     </property>
+     <property name="childrenCollapsible">
+      <bool>false</bool>
+     </property>
+     <widget class="QWidget" name="gridLayoutWidget">
+      <layout class="QGridLayout" name="gridLayout_2" rowstretch="1,2" columnstretch="2,3">
+       <item row="0" column="1">
+        <layout class="QGridLayout" name="gridLayout_3">
+         <item row="2" column="0">
           <widget class="QPushButton" name="m_btnCheckAll">
            <property name="text">
             <string>&amp;Check all</string>
            </property>
           </widget>
          </item>
-         <item>
+         <item row="2" column="2">
+          <spacer name="horizontalSpacer_5">
+           <property name="orientation">
+            <enum>Qt::Horizontal</enum>
+           </property>
+           <property name="sizeHint" stdset="0">
+            <size>
+             <width>40</width>
+             <height>20</height>
+            </size>
+           </property>
+          </spacer>
+         </item>
+         <item row="1" column="0" colspan="3">
+          <widget class="QTreeView" name="m_treeFeeds">
+           <property name="uniformRowHeights">
+            <bool>true</bool>
+           </property>
+           <attribute name="headerVisible">
+            <bool>false</bool>
+           </attribute>
+          </widget>
+         </item>
+         <item row="2" column="1">
           <widget class="QPushButton" name="m_btnUncheckAll">
            <property name="text">
             <string>&amp;Uncheck all</string>
            </property>
           </widget>
          </item>
-         <item>
-          <spacer name="verticalSpacer">
+         <item row="0" column="0" colspan="3">
+          <widget class="QComboBox" name="m_cmbAccounts"/>
+         </item>
+        </layout>
+       </item>
+       <item row="0" column="0">
+        <layout class="QGridLayout" name="gridLayout">
+         <item row="1" column="2">
+          <widget class="QPushButton" name="m_btnRemoveSelected">
+           <property name="text">
+            <string>Remove selected</string>
+           </property>
+          </widget>
+         </item>
+         <item row="1" column="1">
+          <widget class="QPushButton" name="m_btnAddNew">
+           <property name="text">
+            <string>&amp;New filter</string>
+           </property>
+          </widget>
+         </item>
+         <item row="1" column="0">
+          <spacer name="horizontalSpacer">
            <property name="orientation">
-            <enum>Qt::Vertical</enum>
+            <enum>Qt::Horizontal</enum>
            </property>
            <property name="sizeHint" stdset="0">
             <size>
-             <width>20</width>
-             <height>40</height>
+             <width>40</width>
+             <height>20</height>
             </size>
            </property>
           </spacer>
          </item>
+         <item row="0" column="0" colspan="3">
+          <widget class="QListWidget" name="m_listFilters">
+           <property name="uniformItemSizes">
+            <bool>true</bool>
+           </property>
+          </widget>
+         </item>
         </layout>
        </item>
+       <item row="1" column="0" colspan="2">
+        <widget class="QGroupBox" name="m_gbDetails">
+         <property name="title">
+          <string>Message filter details</string>
+         </property>
+         <layout class="QFormLayout" name="formLayout">
+          <item row="0" column="0">
+           <widget class="QLabel" name="label">
+            <property name="text">
+             <string>Title</string>
+            </property>
+            <property name="buddy">
+             <cstring>m_txtTitle</cstring>
+            </property>
+           </widget>
+          </item>
+          <item row="0" column="1">
+           <widget class="QLineEdit" name="m_txtTitle">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="maximumSize">
+             <size>
+              <width>300</width>
+              <height>16777215</height>
+             </size>
+            </property>
+            <property name="placeholderText">
+             <string>Title of message filter</string>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="0">
+           <widget class="QLabel" name="label_2">
+            <property name="text">
+             <string>JavaScript code</string>
+            </property>
+            <property name="buddy">
+             <cstring>m_txtScript</cstring>
+            </property>
+           </widget>
+          </item>
+          <item row="1" column="1">
+           <widget class="QPlainTextEdit" name="m_txtScript">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
+              <horstretch>0</horstretch>
+              <verstretch>1</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="placeholderText">
+             <string>Your JavaScript-based message filtering logic</string>
+            </property>
+           </widget>
+          </item>
+          <item row="2" column="1">
+           <layout class="QHBoxLayout" name="horizontalLayout_2">
+            <item>
+             <widget class="QPushButton" name="m_btnTest">
+              <property name="text">
+               <string>&amp;Test</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QPushButton" name="m_btnRunOnMessages">
+              <property name="text">
+               <string>Process checked feeds</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QPushButton" name="m_btnBeautify">
+              <property name="text">
+               <string>&amp;Beautify</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QPushButton" name="m_btnDetailedHelp">
+              <property name="text">
+               <string>Detailed &amp;help</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <spacer name="horizontalSpacer_3">
+              <property name="orientation">
+               <enum>Qt::Horizontal</enum>
+              </property>
+              <property name="sizeHint" stdset="0">
+               <size>
+                <width>40</width>
+                <height>20</height>
+               </size>
+              </property>
+             </spacer>
+            </item>
+           </layout>
+          </item>
+         </layout>
+        </widget>
+       </item>
       </layout>
-     </item>
-    </layout>
-   </item>
-   <item row="1" column="0" colspan="2">
-    <widget class="QGroupBox" name="m_gbDetails">
-     <property name="title">
-      <string>Message filter details</string>
-     </property>
-     <layout class="QFormLayout" name="formLayout">
-      <item row="0" column="0">
-       <widget class="QLabel" name="label">
-        <property name="text">
-         <string>Title</string>
+     </widget>
+     <widget class="QTabWidget" name="m_twMessages">
+      <property name="sizePolicy">
+       <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
+        <horstretch>1</horstretch>
+        <verstretch>0</verstretch>
+       </sizepolicy>
+      </property>
+      <property name="currentIndex">
+       <number>1</number>
+      </property>
+      <widget class="QWidget" name="m_tabExistingMessages">
+       <attribute name="title">
+        <string>Existing messages</string>
+       </attribute>
+       <layout class="QHBoxLayout" name="horizontalLayout_7">
+        <property name="leftMargin">
+         <number>0</number>
         </property>
-        <property name="buddy">
-         <cstring>m_txtTitle</cstring>
+        <property name="topMargin">
+         <number>0</number>
         </property>
-       </widget>
-      </item>
-      <item row="0" column="1">
-       <layout class="QHBoxLayout" name="horizontalLayout">
-        <item>
-         <widget class="QLineEdit" name="m_txtTitle">
-          <property name="sizePolicy">
-           <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
-            <horstretch>0</horstretch>
-            <verstretch>0</verstretch>
-           </sizepolicy>
-          </property>
-          <property name="maximumSize">
-           <size>
-            <width>300</width>
-            <height>16777215</height>
-           </size>
-          </property>
-          <property name="placeholderText">
-           <string>Title of message filter</string>
-          </property>
-         </widget>
-        </item>
-        <item>
-         <spacer name="horizontalSpacer_2">
-          <property name="orientation">
-           <enum>Qt::Horizontal</enum>
-          </property>
-          <property name="sizeHint" stdset="0">
-           <size>
-            <width>0</width>
-            <height>0</height>
-           </size>
-          </property>
-         </spacer>
-        </item>
-       </layout>
-      </item>
-      <item row="1" column="0">
-       <widget class="QLabel" name="label_2">
-        <property name="text">
-         <string>JavaScript code</string>
+        <property name="rightMargin">
+         <number>0</number>
         </property>
-        <property name="buddy">
-         <cstring>m_txtScript</cstring>
+        <property name="bottomMargin">
+         <number>0</number>
         </property>
-       </widget>
-      </item>
-      <item row="1" column="1">
-       <layout class="QHBoxLayout" name="horizontalLayout_3">
         <item>
-         <widget class="QPlainTextEdit" name="m_txtScript">
-          <property name="placeholderText">
-           <string>Your JavaScript-based message filtering logic</string>
-          </property>
-         </widget>
-        </item>
-        <item>
-         <widget class="QTabWidget" name="m_tcMessage">
-          <property name="currentIndex">
+         <widget class="QTreeView" name="m_treeExistingMessages">
+          <property name="indentation">
            <number>0</number>
           </property>
-          <widget class="QWidget" name="m_tabSample">
-           <attribute name="title">
-            <string>Sample message</string>
-           </attribute>
-           <layout class="QFormLayout" name="formLayout_2">
-            <property name="leftMargin">
-             <number>3</number>
-            </property>
-            <property name="topMargin">
-             <number>3</number>
-            </property>
-            <property name="rightMargin">
-             <number>3</number>
-            </property>
-            <property name="bottomMargin">
-             <number>3</number>
-            </property>
-            <item row="0" column="0" colspan="2">
-             <layout class="QHBoxLayout" name="horizontalLayout_4">
-              <item>
-               <widget class="QCheckBox" name="m_cbSampleRead">
-                <property name="text">
-                 <string>Read</string>
-                </property>
-               </widget>
-              </item>
-              <item>
-               <widget class="QCheckBox" name="m_cbSampleImportant">
-                <property name="text">
-                 <string>Important</string>
-                </property>
-               </widget>
-              </item>
-              <item>
-               <spacer name="horizontalSpacer_4">
-                <property name="orientation">
-                 <enum>Qt::Horizontal</enum>
-                </property>
-                <property name="sizeHint" stdset="0">
-                 <size>
-                  <width>40</width>
-                  <height>20</height>
-                 </size>
-                </property>
-               </spacer>
-              </item>
-             </layout>
-            </item>
-            <item row="1" column="0">
-             <widget class="QLabel" name="label_4">
-              <property name="text">
-               <string>Title</string>
-              </property>
-              <property name="buddy">
-               <cstring>m_txtSampleTitle</cstring>
-              </property>
-             </widget>
-            </item>
-            <item row="1" column="1">
-             <widget class="QLineEdit" name="m_txtSampleTitle"/>
-            </item>
-            <item row="2" column="0">
-             <widget class="QLabel" name="label_6">
-              <property name="text">
-               <string>URL</string>
-              </property>
-              <property name="buddy">
-               <cstring>m_txtSampleUrl</cstring>
-              </property>
-             </widget>
-            </item>
-            <item row="2" column="1">
-             <widget class="QLineEdit" name="m_txtSampleUrl"/>
-            </item>
-            <item row="3" column="0">
-             <widget class="QLabel" name="label_7">
-              <property name="text">
-               <string>Author</string>
-              </property>
-              <property name="buddy">
-               <cstring>m_txtSampleAuthor</cstring>
-              </property>
-             </widget>
-            </item>
-            <item row="3" column="1">
-             <widget class="QLineEdit" name="m_txtSampleAuthor"/>
-            </item>
-            <item row="4" column="0">
-             <widget class="QLabel" name="label_8">
-              <property name="text">
-               <string>Created on</string>
-              </property>
-              <property name="buddy">
-               <cstring>m_txtSampleCreatedOn</cstring>
-              </property>
-             </widget>
-            </item>
-            <item row="4" column="1">
-             <widget class="QLineEdit" name="m_txtSampleCreatedOn"/>
-            </item>
-            <item row="5" column="0">
-             <widget class="QLabel" name="label_5">
-              <property name="text">
-               <string>Contents</string>
-              </property>
-              <property name="buddy">
-               <cstring>m_txtSampleContents</cstring>
-              </property>
-             </widget>
-            </item>
-            <item row="5" column="1">
-             <widget class="QPlainTextEdit" name="m_txtSampleContents"/>
-            </item>
-           </layout>
-          </widget>
-          <widget class="QWidget" name="m_tabScriptOutput">
-           <attribute name="title">
-            <string>Script output</string>
-           </attribute>
-           <layout class="QHBoxLayout" name="horizontalLayout_6">
-            <property name="leftMargin">
-             <number>3</number>
-            </property>
-            <property name="topMargin">
-             <number>3</number>
-            </property>
-            <property name="rightMargin">
-             <number>3</number>
-            </property>
-            <property name="bottomMargin">
-             <number>3</number>
-            </property>
-            <item>
-             <widget class="QTextEdit" name="m_txtErrors">
-              <property name="sizePolicy">
-               <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
-                <horstretch>0</horstretch>
-                <verstretch>1</verstretch>
-               </sizepolicy>
-              </property>
-             </widget>
-            </item>
-           </layout>
-          </widget>
+          <property name="uniformRowHeights">
+           <bool>true</bool>
+          </property>
+          <property name="itemsExpandable">
+           <bool>false</bool>
+          </property>
          </widget>
         </item>
        </layout>
-      </item>
-      <item row="2" column="1">
-       <layout class="QHBoxLayout" name="horizontalLayout_2">
-        <item>
-         <widget class="QPushButton" name="m_btnTest">
+      </widget>
+      <widget class="QWidget" name="m_tabSampleMessage">
+       <attribute name="title">
+        <string>Sample message</string>
+       </attribute>
+       <layout class="QFormLayout" name="formLayout_2">
+        <property name="leftMargin">
+         <number>0</number>
+        </property>
+        <property name="topMargin">
+         <number>0</number>
+        </property>
+        <property name="rightMargin">
+         <number>0</number>
+        </property>
+        <property name="bottomMargin">
+         <number>0</number>
+        </property>
+        <item row="1" column="0">
+         <widget class="QLabel" name="label_4">
           <property name="text">
-           <string>&amp;Test!</string>
+           <string>Title</string>
+          </property>
+          <property name="buddy">
+           <cstring>m_txtSampleTitle</cstring>
           </property>
          </widget>
         </item>
-        <item>
-         <widget class="QPushButton" name="m_btnBeautify">
+        <item row="1" column="1">
+         <widget class="QLineEdit" name="m_txtSampleTitle"/>
+        </item>
+        <item row="2" column="0">
+         <widget class="QLabel" name="label_6">
           <property name="text">
-           <string>&amp;Beautify!</string>
+           <string>URL</string>
+          </property>
+          <property name="buddy">
+           <cstring>m_txtSampleUrl</cstring>
           </property>
          </widget>
         </item>
-        <item>
-         <widget class="QPushButton" name="m_btnDetailedHelp">
+        <item row="2" column="1">
+         <widget class="QLineEdit" name="m_txtSampleUrl"/>
+        </item>
+        <item row="3" column="0">
+         <widget class="QLabel" name="label_7">
           <property name="text">
-           <string>Detailed &amp;help</string>
+           <string>Author</string>
+          </property>
+          <property name="buddy">
+           <cstring>m_txtSampleAuthor</cstring>
           </property>
          </widget>
         </item>
-        <item>
-         <spacer name="horizontalSpacer_3">
-          <property name="orientation">
-           <enum>Qt::Horizontal</enum>
+        <item row="3" column="1">
+         <widget class="QLineEdit" name="m_txtSampleAuthor"/>
+        </item>
+        <item row="4" column="0">
+         <widget class="QLabel" name="label_8">
+          <property name="text">
+           <string>Created on</string>
           </property>
-          <property name="sizeHint" stdset="0">
-           <size>
-            <width>40</width>
-            <height>20</height>
-           </size>
+          <property name="buddy">
+           <cstring>m_txtSampleCreatedOn</cstring>
           </property>
-         </spacer>
+         </widget>
+        </item>
+        <item row="4" column="1">
+         <widget class="QLineEdit" name="m_txtSampleCreatedOn"/>
+        </item>
+        <item row="5" column="0">
+         <widget class="QLabel" name="label_5">
+          <property name="text">
+           <string>Contents</string>
+          </property>
+          <property name="buddy">
+           <cstring>m_txtSampleContents</cstring>
+          </property>
+         </widget>
+        </item>
+        <item row="5" column="1">
+         <widget class="QPlainTextEdit" name="m_txtSampleContents"/>
+        </item>
+        <item row="0" column="0" colspan="2">
+         <layout class="QHBoxLayout" name="horizontalLayout_4">
+          <item>
+           <widget class="QCheckBox" name="m_cbSampleRead">
+            <property name="text">
+             <string>Read</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QCheckBox" name="m_cbSampleImportant">
+            <property name="text">
+             <string>Important</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <spacer name="horizontalSpacer_4">
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>40</width>
+              <height>20</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+         </layout>
         </item>
        </layout>
-      </item>
-     </layout>
+      </widget>
+      <widget class="QWidget" name="m_tabOutput">
+       <attribute name="title">
+        <string>Script output</string>
+       </attribute>
+       <layout class="QHBoxLayout" name="horizontalLayout">
+        <property name="leftMargin">
+         <number>0</number>
+        </property>
+        <property name="topMargin">
+         <number>0</number>
+        </property>
+        <property name="rightMargin">
+         <number>0</number>
+        </property>
+        <property name="bottomMargin">
+         <number>0</number>
+        </property>
+        <item>
+         <widget class="QTextEdit" name="m_txtErrors">
+          <property name="sizePolicy">
+           <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
+            <horstretch>0</horstretch>
+            <verstretch>1</verstretch>
+           </sizepolicy>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </widget>
+     </widget>
     </widget>
    </item>
-   <item row="2" column="1">
+   <item>
     <widget class="QDialogButtonBox" name="m_buttonBox">
      <property name="orientation">
       <enum>Qt::Horizontal</enum>
@@ -411,17 +432,11 @@
   <tabstop>m_txtTitle</tabstop>
   <tabstop>m_txtScript</tabstop>
   <tabstop>m_btnTest</tabstop>
+  <tabstop>m_btnRunOnMessages</tabstop>
   <tabstop>m_btnBeautify</tabstop>
   <tabstop>m_btnDetailedHelp</tabstop>
-  <tabstop>m_tcMessage</tabstop>
-  <tabstop>m_cbSampleRead</tabstop>
-  <tabstop>m_cbSampleImportant</tabstop>
-  <tabstop>m_txtSampleTitle</tabstop>
-  <tabstop>m_txtSampleUrl</tabstop>
-  <tabstop>m_txtSampleAuthor</tabstop>
-  <tabstop>m_txtSampleCreatedOn</tabstop>
-  <tabstop>m_txtSampleContents</tabstop>
-  <tabstop>m_txtErrors</tabstop>
+  <tabstop>m_twMessages</tabstop>
+  <tabstop>m_treeExistingMessages</tabstop>
  </tabstops>
  <resources/>
  <connections>
diff --git a/src/librssguard/librssguard.pro b/src/librssguard/librssguard.pro
index e0de68e54..b3752738e 100644
--- a/src/librssguard/librssguard.pro
+++ b/src/librssguard/librssguard.pro
@@ -38,6 +38,7 @@ HEADERS += core/feeddownloader.h \
            core/message.h \
            core/messagefilter.h \
            core/messageobject.h \
+           core/messagesforfiltersmodel.h \
            core/messagesmodel.h \
            core/messagesmodelcache.h \
            core/messagesmodelsqllayer.h \
@@ -195,6 +196,7 @@ SOURCES += core/feeddownloader.cpp \
            core/message.cpp \
            core/messagefilter.cpp \
            core/messageobject.cpp \
+           core/messagesforfiltersmodel.cpp \
            core/messagesmodel.cpp \
            core/messagesmodelcache.cpp \
            core/messagesmodelsqllayer.cpp \
diff --git a/src/librssguard/miscellaneous/skinfactory.h b/src/librssguard/miscellaneous/skinfactory.h
index 0c174c412..9c6b7073a 100644
--- a/src/librssguard/miscellaneous/skinfactory.h
+++ b/src/librssguard/miscellaneous/skinfactory.h
@@ -13,7 +13,8 @@
 struct RSSGUARD_DLLSPEC Skin {
   enum class PaletteColors {
     Highlight = 1,
-    Error = 2
+    Error = 2,
+    Allright = 3
   };
 
   QString m_baseName;