--- a/configure
+++ b/configure
@@ -662,8 +662,8 @@
 QT_LIB
 QT_CFLAGS
 QT_INC
-qt5_LIBS
-qt5_CFLAGS
+qt6_LIBS
+qt6_CFLAGS
 ffmpeg_LIBS
 ffmpeg_CFLAGS
 PKG_CONFIG_LIBDIR
@@ -777,7 +777,7 @@
 with_sysroot
 enable_libtool_lock
 enable_gui
-enable_qt5
+enable_qt6
 enable_noec
 enable_debug
 '
@@ -800,8 +800,8 @@
 PKG_CONFIG_LIBDIR
 ffmpeg_CFLAGS
 ffmpeg_LIBS
-qt5_CFLAGS
-qt5_LIBS'
+qt6_CFLAGS
+qt6_LIBS'
 
 
 # Initialize some variables set by options.
@@ -1431,7 +1431,7 @@
                           optimize for fast installation [default=yes]
   --disable-libtool-lock  avoid locking (might break parallel builds)
   --disable-gui           do not build GUI (default is build GUI)
-  --disable-qt5           do not use Qt5
+  --disable-qt6           do not use Qt6
   --enable-noec           use private ECDSA code (default - use openssl ECDSA
                           if available)
   --enable-debug          keep debug symbols in binarfies (default - strip
@@ -1471,8 +1471,8 @@
   ffmpeg_CFLAGS
               C compiler flags for ffmpeg, overriding pkg-config
   ffmpeg_LIBS linker flags for ffmpeg, overriding pkg-config
-  qt5_CFLAGS  C compiler flags for qt5, overriding pkg-config
-  qt5_LIBS    linker flags for qt5, overriding pkg-config
+  qt6_CFLAGS  C compiler flags for qt6, overriding pkg-config
+  qt6_LIBS    linker flags for qt6, overriding pkg-config
 
 Use these variables to override the choices made by `configure' or to help
 it to find libraries and programs with nonstandard names/locations.
@@ -12545,12 +12545,12 @@
 
 #AM_CONDITIONAL([ENABLE_GUI],[test "x$enable_gui" = "xyes"])
 
-# Check whether --enable-qt5 was given.
-if test ${enable_qt5+y}
+# Check whether --enable-qt6 was given.
+if test ${enable_qt6+y}
 then :
-  enableval=$enable_qt5;
+  enableval=$enable_qt6;
 else $as_nop
-  enable_qt5=yes
+  enable_qt6=yes
 fi
 
 
@@ -17312,7 +17312,7 @@
 test -z "$INSTALL_DATA" && INSTALL_DATA='${INSTALL} -m 644'
 
 
-  ax_cxx_compile_alternatives="11 0x"    ax_cxx_compile_cxx11_required=true
+  ax_cxx_compile_alternatives="17"    ax_cxx_compile_cxx11_required=true
   ac_ext=cpp
 ac_cpp='$CXXCPP $CPPFLAGS'
 ac_compile='$CXX -c $CXXFLAGS $CPPFLAGS conftest.$ac_ext >&5'
@@ -18295,24 +18295,24 @@
 if test "x$enable_gui" != "xno"
 then :
 
-  if test "x$enable_qt5" != "xno"
+  if test "x$enable_qt6" != "xno"
 then :
 
 
 pkg_failed=no
-{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for Qt5Core Qt5Gui Qt5Widgets Qt5DBus" >&5
-printf %s "checking for Qt5Core Qt5Gui Qt5Widgets Qt5DBus... " >&6; }
+{ printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking for Qt6Core Qt6Gui Qt6Widgets Qt6DBus" >&5
+printf %s "checking for Qt6Core Qt6Gui Qt6Widgets Qt6DBus... " >&6; }
 
-if test -n "$qt5_CFLAGS"; then
-    pkg_cv_qt5_CFLAGS="$qt5_CFLAGS"
+if test -n "$qt6_CFLAGS"; then
+    pkg_cv_qt6_CFLAGS="$qt6_CFLAGS"
  elif test -n "$PKG_CONFIG"; then
     if test -n "$PKG_CONFIG" && \
-    { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"Qt5Core Qt5Gui Qt5Widgets Qt5DBus\""; } >&5
-  ($PKG_CONFIG --exists --print-errors "Qt5Core Qt5Gui Qt5Widgets Qt5DBus") 2>&5
+    { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"Qt6Core Qt6Gui Qt6Widgets Qt6DBus\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "Qt6Core Qt6Gui Qt6Widgets Qt6DBus") 2>&5
   ac_status=$?
   printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
-  pkg_cv_qt5_CFLAGS=`$PKG_CONFIG --cflags "Qt5Core Qt5Gui Qt5Widgets Qt5DBus" 2>/dev/null`
+  pkg_cv_qt6_CFLAGS=`$PKG_CONFIG --cflags "Qt6Core Qt6Gui Qt6Widgets Qt6DBus" 2>/dev/null`
 		      test "x$?" != "x0" && pkg_failed=yes
 else
   pkg_failed=yes
@@ -18320,16 +18320,16 @@
  else
     pkg_failed=untried
 fi
-if test -n "$qt5_LIBS"; then
-    pkg_cv_qt5_LIBS="$qt5_LIBS"
+if test -n "$qt6_LIBS"; then
+    pkg_cv_qt6_LIBS="$qt6_LIBS"
  elif test -n "$PKG_CONFIG"; then
     if test -n "$PKG_CONFIG" && \
-    { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"Qt5Core Qt5Gui Qt5Widgets Qt5DBus\""; } >&5
-  ($PKG_CONFIG --exists --print-errors "Qt5Core Qt5Gui Qt5Widgets Qt5DBus") 2>&5
+    { { printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$PKG_CONFIG --exists --print-errors \"Qt6Core Qt6Gui Qt6Widgets Qt6DBus\""; } >&5
+  ($PKG_CONFIG --exists --print-errors "Qt6Core Qt6Gui Qt6Widgets Qt6DBus") 2>&5
   ac_status=$?
   printf "%s\n" "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
   test $ac_status = 0; }; then
-  pkg_cv_qt5_LIBS=`$PKG_CONFIG --libs "Qt5Core Qt5Gui Qt5Widgets Qt5DBus" 2>/dev/null`
+  pkg_cv_qt6_LIBS=`$PKG_CONFIG --libs "Qt6Core Qt6Gui Qt6Widgets Qt6DBus" 2>/dev/null`
 		      test "x$?" != "x0" && pkg_failed=yes
 else
   pkg_failed=yes
@@ -18350,12 +18350,12 @@
         _pkg_short_errors_supported=no
 fi
         if test $_pkg_short_errors_supported = yes; then
-                qt5_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors --cflags --libs "Qt5Core Qt5Gui Qt5Widgets Qt5DBus" 2>&1`
+                qt6_PKG_ERRORS=`$PKG_CONFIG --short-errors --print-errors --cflags --libs "Qt6Core Qt6Gui Qt6Widgets Qt6DBus" 2>&1`
         else
-                qt5_PKG_ERRORS=`$PKG_CONFIG --print-errors --cflags --libs "Qt5Core Qt5Gui Qt5Widgets Qt5DBus" 2>&1`
+                qt6_PKG_ERRORS=`$PKG_CONFIG --print-errors --cflags --libs "Qt6Core Qt6Gui Qt6Widgets Qt6DBus" 2>&1`
         fi
         # Put the nasty error message in config.log where it belongs
-        echo "$qt5_PKG_ERRORS" >&5
+        echo "$qt6_PKG_ERRORS" >&5
 
         qt_ok=no
 elif test $pkg_failed = untried; then
@@ -18363,16 +18363,16 @@
 printf "%s\n" "no" >&6; }
         qt_ok=no
 else
-        qt5_CFLAGS=$pkg_cv_qt5_CFLAGS
-        qt5_LIBS=$pkg_cv_qt5_LIBS
+        qt6_CFLAGS=$pkg_cv_qt6_CFLAGS
+        qt6_LIBS=$pkg_cv_qt6_LIBS
         { printf "%s\n" "$as_me:${as_lineno-$LINENO}: result: yes" >&5
 printf "%s\n" "yes" >&6; }
 
-      QT_INC="$qt5_CFLAGS";
+      QT_INC="$qt6_CFLAGS";
       QT_CFLAGS="-fPIC";
-      QT_LIB="$qt5_LIBS";
-      qt5_host_bins=`$PKG_CONFIG --variable host_bins "Qt5Core" 2>/dev/null`;
-      QT_MOC="$qt5_host_bins/moc";
+      QT_LIB="$qt6_LIBS";
+      qt6_libexecdir=`$PKG_CONFIG --variable libexecdir "Qt6Core" 2>/dev/null`;
+      QT_MOC="$qt6_libexecdir/moc";
       qt_ok=yes
 
 fi
--- a/makemkvgui/src/dirselectbox.cpp
+++ b/makemkvgui/src/dirselectbox.cpp
@@ -121,7 +121,7 @@
             if ( (dir.at(dlen-(alen+1))==QLatin1Char('/')) ||
                  (dir.at(dlen-(alen+1))==QLatin1Char('\\')) )
             {
-                if (dir.endsWith(appendName)) {
+                if (dir.endsWith(*appendName)) {
                     dir.chop(alen+1);
                 }
             }
--- a/makemkvgui/src/mainwnd.cpp
+++ b/makemkvgui/src/mainwnd.cpp
@@ -35,7 +35,7 @@
     Qt::MacWindowToolBarButtonHint |
     Qt::WindowMinMaxButtonsHint ;
 #else
-    0;
+    Qt::Widget;
 #endif
 
 MainWnd::MainWnd(CGUIApClient* App,const char* AppDir)
--- a/makemkvgui/src/qtgui.h
+++ b/makemkvgui/src/qtgui.h
@@ -46,7 +46,7 @@
 #include <QtWidgets/QProgressBar>
 #include <QtWidgets/QStackedWidget>
 #include <QtWidgets/QComboBox>
-#include <QtWidgets/QAction>
+#include <QtGui/QAction>
 #include <QtWidgets/QCheckBox>
 #include <QtWidgets/QGridLayout>
 #include <QtWidgets/QBoxLayout>
