diff --git a/.github/workflows/ubuntu-6.2.yml b/.github/workflows/ubuntu-6.2.yml
index 2b12c07b..5ffcd5ba 100644
--- a/.github/workflows/ubuntu-6.2.yml
+++ b/.github/workflows/ubuntu-6.2.yml
@@ -54,6 +54,7 @@ jobs:
           sudo apt-get install libxtst-dev liblzo2-dev libbz2-dev 
           sudo apt-get install libao-dev libavutil-dev libavformat-dev libtiff5-dev libeb16-dev 
           sudo apt-get install doxygen libzstd-dev libxkbcommon-dev libgstreamer-plugins-base1.0-0 libgstreamer-gl1.0-0
+          sudo apt install libfuse2
           sudo ln -sf /usr/bin/x86_64-linux-gnu-ld.gold /usr/bin/ld
           
           #build opencc
diff --git a/article-style-st-classic.css b/article-style-st-classic.css
index 9a5155ca..fd7d9c57 100644
--- a/article-style-st-classic.css
+++ b/article-style-st-classic.css
@@ -390,7 +390,7 @@ div.xdxf
   display:inline;
 }
 
-.dsl_article font[color=c_default_color]
+.dsl_article .c_default_color
 {
   color: green;
 }
diff --git a/article-style.css b/article-style.css
index 99e88dff..ee6cc077 100644
--- a/article-style.css
+++ b/article-style.css
@@ -396,7 +396,7 @@ div.xdxf
   display:inline;
 }
 
-.dsl_article font[color=c_default_color]
+.dsl_article .c_default_color
 {
   color: green;
 }
diff --git a/articleview.cc b/articleview.cc
index 54fb14db..4dfd0aab 100644
--- a/articleview.cc
+++ b/articleview.cc
@@ -2149,9 +2149,9 @@ void ArticleView::resourceDownloadFinished()
 
   if ( resourceDownloadRequests.empty() )
   {
-    emit statusBarMessage(
-        tr("WARNING: %1").arg(tr("The referenced resource failed to download.")),
-        10000, QPixmap(":/icons/error.svg"));
+    // emit statusBarMessage(
+    //     tr("WARNING: %1").arg(tr("The referenced resource failed to download.")),
+    //     10000, QPixmap(":/icons/error.svg"));
   }
 }
 
diff --git a/config.cc b/config.cc
index 0dd18f01..48ca3103 100644
--- a/config.cc
+++ b/config.cc
@@ -219,6 +219,7 @@ Preferences::Preferences():
   selectWordBySingleClick( false ),
   autoScrollToTargetArticle( true ),
   escKeyHidesMainWindow( false ),
+  darkMode( false ),
   alwaysOnTop ( false ),
   searchInDock ( false ),
 
@@ -869,6 +870,9 @@ Class load()
     if ( !preferences.namedItem( "escKeyHidesMainWindow" ).isNull() )
       c.preferences.escKeyHidesMainWindow = ( preferences.namedItem( "escKeyHidesMainWindow" ).toElement().text() == "1" );
 
+    if ( !preferences.namedItem( "darkMode" ).isNull() )
+      c.preferences.darkMode = ( preferences.namedItem( "darkMode" ).toElement().text() == "1" );
+
     if ( !preferences.namedItem( "zoomFactor" ).isNull() )
       c.preferences.zoomFactor = preferences.namedItem( "zoomFactor" ).toElement().text().toDouble();
 
@@ -1711,6 +1715,10 @@ void save( Class const & c )
     opt.appendChild( dd.createTextNode( c.preferences.escKeyHidesMainWindow ? "1":"0" ) );
     preferences.appendChild( opt );
 
+    opt = dd.createElement( "darkMode" );
+    opt.appendChild( dd.createTextNode( c.preferences.darkMode ? "1":"0" ) );
+    preferences.appendChild( opt );
+
     opt = dd.createElement( "zoomFactor" );
     opt.appendChild( dd.createTextNode( QString::number( c.preferences.zoomFactor ) ) );
     preferences.appendChild( opt );
diff --git a/config.hh b/config.hh
index 402723c9..b2ce2d7c 100644
--- a/config.hh
+++ b/config.hh
@@ -307,6 +307,7 @@ struct Preferences
   bool selectWordBySingleClick;
   bool autoScrollToTargetArticle;
   bool escKeyHidesMainWindow;
+  bool darkMode;
   bool alwaysOnTop;
 
   /// An old UI mode when tranlateLine and wordList
diff --git a/dsl.cc b/dsl.cc
index a808b48b..32eab1f9 100644
--- a/dsl.cc
+++ b/dsl.cc
@@ -809,9 +809,17 @@ string DslDictionary::nodeToHtml( ArticleDom::Node const & node )
   }
   else if( node.tagName ==  U"c"  )
   {
-    result += "<font color=\"" + ( node.tagAttrs.size() ?
-      Html::escape( Utf8::encode( node.tagAttrs ) ) : string( "c_default_color" ) )
-      + "\">" + processNodeChildren( node ) + "</font>";
+    if( node.tagAttrs.empty() )
+    {
+      result += "<span class=\"c_default_color\">"
+        + processNodeChildren( node ) + "</span>";
+    }
+    else
+    {
+      result += "<font color=\""
+        + Html::escape( Utf8::encode( node.tagAttrs ) ) + "\">"
+        + processNodeChildren( node ) + "</font>";
+    }
   }
   else if( node.tagName ==  U"*"  )
   {
diff --git a/ffmpegaudio.cc b/ffmpegaudio.cc
index 60e21213..5674b432 100644
--- a/ffmpegaudio.cc
+++ b/ffmpegaudio.cc
@@ -186,7 +186,7 @@ bool DecoderContext::openCodec( QString & errorString )
   int ret = 0;
   avformatOpened_ = true;
 
-  ret = avformat_open_input( &formatContext_, "_STREAM_", NULL, NULL );
+  ret = avformat_open_input( &formatContext_, NULL, NULL, NULL );
   if ( ret < 0 )
   {
     errorString = QObject::tr( "avformat_open_input() failed: %1." ).arg( avErrorString( ret ) );
diff --git a/mainwindow.cc b/mainwindow.cc
index 743af1a0..6511c672 100644
--- a/mainwindow.cc
+++ b/mainwindow.cc
@@ -834,7 +834,7 @@ MainWindow::MainWindow( Config::Class & cfg_ ):
 
   translateLine->setFocus();
 
-  applyQtStyleSheet( cfg.preferences.displayStyle, cfg.preferences.addonStyle );
+  applyQtStyleSheet( cfg.preferences.displayStyle, cfg.preferences.addonStyle, cfg.preferences.darkMode );
 
   makeScanPopup();
 
@@ -1175,8 +1175,45 @@ QPrinter & MainWindow::getPrinter()
   return *printer;
 }
 
-void MainWindow::applyQtStyleSheet( QString const & displayStyle, QString const & addonStyle )
+void MainWindow::applyQtStyleSheet( QString const & displayStyle, QString const & addonStyle, bool const & darkMode )
 {
+  if( darkMode )
+  {
+    //https://forum.qt.io/topic/101391/windows-10-dark-theme
+    #ifdef Q_OS_WIN32
+    qApp->setStyle( QStyleFactory::create( "Fusion" ) );
+    #endif
+    QPalette darkPalette;
+    QColor darkColor     = QColor( 45, 45, 45 );
+    QColor disabledColor = QColor( 127, 127, 127 );
+    darkPalette.setColor( QPalette::Window, darkColor );
+    darkPalette.setColor( QPalette::WindowText, Qt::white );
+    darkPalette.setColor( QPalette::Base, QColor( 18, 18, 18 ) );
+    darkPalette.setColor( QPalette::AlternateBase, darkColor );
+    darkPalette.setColor( QPalette::ToolTipBase, Qt::white );
+    darkPalette.setColor( QPalette::ToolTipText, Qt::white );
+    darkPalette.setColor( QPalette::Text, Qt::white );
+    darkPalette.setColor( QPalette::Disabled, QPalette::Text, disabledColor );
+    darkPalette.setColor( QPalette::Button, darkColor );
+    darkPalette.setColor( QPalette::ButtonText, Qt::white );
+    darkPalette.setColor( QPalette::Disabled, QPalette::ButtonText, disabledColor );
+    darkPalette.setColor( QPalette::BrightText, Qt::red );
+    darkPalette.setColor( QPalette::Link, QColor( 42, 130, 218 ) );
+
+    darkPalette.setColor( QPalette::Highlight, QColor( 42, 130, 218 ) );
+    darkPalette.setColor( QPalette::HighlightedText, Qt::black );
+    darkPalette.setColor( QPalette::Disabled, QPalette::HighlightedText, disabledColor );
+
+    qApp->setPalette( darkPalette );
+  }
+  else
+  {
+  #ifdef Q_OS_WIN32
+    qApp->setStyle( QStyleFactory::create( "Windows" ) );
+  #endif
+    qApp->setPalette( QPalette() );
+  }
+
   QFile builtInCssFile( ":/qt-style.css" );
   builtInCssFile.open( QFile::ReadOnly );
   QByteArray css = builtInCssFile.readAll();
@@ -1210,6 +1247,10 @@ void MainWindow::applyQtStyleSheet( QString const & displayStyle, QString const
       css += addonCss.readAll();
   }
 
+  if(darkMode){
+    css += "QToolTip { color: #ffffff; background-color: #2a82da; border: 1px solid white; }";
+  }
+
   setStyleSheet( css );
 }
 
@@ -2237,9 +2278,9 @@ void MainWindow::editPreferences()
     bool needReload = false;
 
     // See if we need to reapply stylesheets
-    if ( cfg.preferences.displayStyle != p.displayStyle || cfg.preferences.addonStyle != p.addonStyle )
+    if ( cfg.preferences.displayStyle != p.displayStyle || cfg.preferences.addonStyle != p.addonStyle || cfg.preferences.darkMode != p.darkMode)
     {
-      applyQtStyleSheet( p.displayStyle, p.addonStyle );
+      applyQtStyleSheet( p.displayStyle, p.addonStyle, p.darkMode );
       articleMaker.setDisplayStyle( p.displayStyle, p.addonStyle );
       needReload = true;
     }
diff --git a/mainwindow.hh b/mainwindow.hh
index b57c1ba1..346e0c5b 100644
--- a/mainwindow.hh
+++ b/mainwindow.hh
@@ -184,7 +184,7 @@ private:
   ResourceSchemeHandler * resourceSchemeHandler;
 
   /// Applies the qt's stylesheet, given the style's name.
-  void applyQtStyleSheet( QString const & displayStyle, QString const & addonStyle );
+  void applyQtStyleSheet( QString const & displayStyle, QString const & addonStyle, bool const & darkMode );
 
   /// Creates, destroys or otherwise updates tray icon, according to the
   /// current configuration and situation.
diff --git a/preferences.cc b/preferences.cc
index 96d693d7..f08380b5 100644
--- a/preferences.cc
+++ b/preferences.cc
@@ -181,6 +181,7 @@ Preferences::Preferences( QWidget * parent, Config::Class & cfg_ ):
   ui.selectBySingleClick->setChecked( p.selectWordBySingleClick);
   ui.autoScrollToTargetArticle->setChecked( p.autoScrollToTargetArticle );
   ui.escKeyHidesMainWindow->setChecked( p.escKeyHidesMainWindow );
+  ui.darkMode->setChecked(p.darkMode);
 
   ui.enableMainWindowHotkey->setChecked( p.enableMainWindowHotkey );
   ui.mainWindowHotkey->setHotKey( p.mainWindowHotkey );
@@ -400,6 +401,7 @@ Config::Preferences Preferences::getPreferences()
   p.autoScrollToTargetArticle = ui.autoScrollToTargetArticle->isChecked();
   p.escKeyHidesMainWindow = ui.escKeyHidesMainWindow->isChecked();
 
+  p.darkMode = ui.darkMode->isChecked();
   p.enableMainWindowHotkey = ui.enableMainWindowHotkey->isChecked();
   p.mainWindowHotkey = ui.mainWindowHotkey->getHotKey();
   p.enableClipboardHotkey = ui.enableClipboardHotkey->isChecked();
diff --git a/preferences.ui b/preferences.ui
index a9e9c159..f3c0403b 100644
--- a/preferences.ui
+++ b/preferences.ui
@@ -412,6 +412,13 @@ be the last ones.</string>
          </item>
         </layout>
        </item>
+       <item row="12" column="0">
+        <widget class="QCheckBox" name="darkMode">
+         <property name="text">
+          <string>dark mode</string>
+         </property>
+        </widget>
+       </item>
       </layout>
      </widget>
      <widget class="QWidget" name="tab_4">