diff --git a/project/bundles/appimage/01-build-centos6.sh b/project/bundles/appimage/01-build-centos6.sh
index 479648a259..ebb228574b 100755
--- a/project/bundles/appimage/01-build-centos6.sh
+++ b/project/bundles/appimage/01-build-centos6.sh
@@ -1,245 +1,245 @@
 #!/bin/bash
 
 # Script to build a CentOS 6 installation to compile an AppImage bundle of digiKam.
 # This script must be run as sudo
 #
 # Copyright (c) 2015-2019, Gilles Caulier, <caulier dot gilles at gmail dot com>
 #
 # Redistribution and use is allowed according to the terms of the BSD license.
 # For details see the accompanying COPYING-CMAKE-SCRIPTS file.
 #
 
 # Halt and catch errors
 set -eE
 trap 'PREVIOUS_COMMAND=$THIS_COMMAND; THIS_COMMAND=$BASH_COMMAND' DEBUG
 trap 'echo "FAILED COMMAND: $PREVIOUS_COMMAND"' ERR
 
 #################################################################################################
 # Manage script traces to log file
 
 mkdir -p ./logs
 exec > >(tee ./logs/build-centos6.full.log) 2>&1
 
 #################################################################################################
 
 echo "01-build-centos6.sh : build a CentOS 6 installation to compile an AppImage of digiKam."
 echo "--------------------------------------------------------------------------------------"
 
 #################################################################################################
 # Pre-processing checks
 
 . ./config.sh
 . ./common.sh
 ChecksRunAsRoot
 StartScript
 ChecksCPUCores
 CentOS6Adjustments
 ORIG_WD="`pwd`"
 
 #################################################################################################
 
 echo -e "---------- Update Linux CentOS 6\n"
 
 yum -y install epel-release
 
 if [[ "$(arch)" = "x86_64" ]] ; then
 
     yum upgrade ca-certificates --disablerepo=epel
 
 fi
 
 if [[ ! -f /etc/yum.repos.d/epel.repo ]] ; then
 
     yum install epel-release
 
     # we need to be up to date in order to install the xcb-keysyms dependency
     yum -y update
 fi
 
 #################################################################################################
 
 echo -e "---------- Install New Development Packages\n"
 
 # Packages for base dependencies and Qt5.
 yum -y install wget \
                tar \
                bzip2 \
                gettext \
                git \
                subversion \
                libtool \
                which \
                fuse \
                automake \
                mesa-libEGL \
                cmake3 \
                gcc-c++ \
                patch \
                libxcb \
                xcb-util \
                xkeyboard-config \
                gperf \
                ruby \
                bison \
                flex \
                zlib-devel \
                expat-devel \
                fuse-devel \
                libtool-ltdl-devel \
                glib2-devel \
                glibc-headers \
                mysql-devel \
                eigen3-devel \
                openssl-devel \
                cppunit-devel \
                libstdc++-devel \
                freetype-devel \
                fontconfig-devel \
                libxml2-devel \
                libstdc++-devel \
                libXrender-devel \
                lcms2-devel \
                xcb-util-keysyms-devel \
                libXi-devel \
                mesa-libGL-devel \
                mesa-libGLU-devel \
                libxcb-devel \
                xcb-util-devel \
                glibc-devel \
                libudev-devel \
                libicu-devel \
                sqlite-devel \
                libusb-devel \
                libexif-devel \
                libical-devel \
                libxslt-devel \
                xz-devel \
                lz4-devel \
                inotify-tools-devel \
                openssl-devel \
                cups-devel \
                openal-soft-devel \
                libical-devel
 
 #################################################################################################
 
 yum -y --nogpgcheck install centos-release-scl
 
 if [[ ! -f /opt/rh/python27/enable ]] ; then
 
     echo -e "---------- Install New Python Interpreter\n"
     yum -y --nogpgcheck install python27
 
 fi
 
 
-if [[ ! -f /opt/rh/devtoolset-4/enable ]] ; then
+if [[ ! -f /opt/rh/devtoolset-7/enable ]] ; then
 
     echo -e "---------- Install New Compiler Tools Set\n"
-    yum -y --nogpgcheck install devtoolset-4-gcc devtoolset-4-gcc-c++
+    yum -y --nogpgcheck install devtoolset-7-gcc devtoolset-7-gcc-c++
 
 fi
 
 #################################################################################################
 
 # Install new repo to get ffmpeg dependencies
 
 if [[ ! -f /etc/yum.repos.d/nux-dextop.repo ]] ; then
 
     echo -e "---------- Install Repository for ffmpeg packages\n"
 
     if [[ "$(arch)" = "x86_64" ]] ; then
 
         rpm --import http://li.nux.ro/download/nux/RPM-GPG-KEY-nux.ro
         rpm -Uvh http://li.nux.ro/download/nux/dextop/el6/x86_64/nux-dextop-release-0-2.el6.nux.noarch.rpm
 
     else
 
         rpm --import http://li.nux.ro/download/nux/RPM-GPG-KEY-nux.ro
         rpm -Uvh http://li.nux.ro/download/nux/dextop/el6/i386/nux-dextop-release-0-2.el6.nux.noarch.rpm
 
     fi
 
 fi
 
 yum -y install libass-devel \
                fdk-aac-devel \
                faac-devel \
                lame-devel \
                opencore-amr-devel \
                opus-devel \
                librtmp-devel \
                speex-devel \
                libtheora-devel \
                libvorbis-devel \
                libvpx-devel \
                x264-devel \
                x265-devel \
                xvidcore-devel \
                yasm
 
 #################################################################################################
 
 echo -e "---------- Clean-up Old Packages\n"
 
 # Remove system based devel package to prevent conflict with new one.
 yum -y erase qt-devel boost-devel libgphoto2 sane-backends libjpeg-devel jasper-devel libpng-devel libtiff-devel ffmpeg ffmpeg-devel ant pulseaudio-libs-devel
 
 #################################################################################################
 
 echo -e "---------- Prepare CentOS to Compile Extra Dependencies\n"
 
 # Workaround for: On CentOS 6, .pc files in /usr/lib/pkgconfig are not recognized
 # However, this is where .pc files get installed when bulding libraries... (FIXME)
 # I found this by comparing the output of librevenge's "make install" command
 # between Ubuntu and CentOS 6
 ln -sf /usr/share/pkgconfig /usr/lib/pkgconfig
 
 # Make sure we build from the /, parts of this script depends on that. We also need to run as root...
 cd /
 
 # Create the build dir for the 3rdparty deps
 if [ ! -d $BUILDING_DIR ] ; then
     mkdir $BUILDING_DIR
 fi
 if [ ! -d $DOWNLOAD_DIR ] ; then
     mkdir $DOWNLOAD_DIR
 fi
 
 # enable new compiler
-. /opt/rh/devtoolset-4/enable
+. /opt/rh/devtoolset-7/enable
 
 # enable new Python
 . /opt/rh/python27/enable
 
 #################################################################################################
 
 cd $BUILDING_DIR
 
 rm -rf $BUILDING_DIR/* || true
 
 cmake3 $ORIG_WD/../3rdparty \
        -DCMAKE_INSTALL_PREFIX:PATH=/usr \
        -DINSTALL_ROOT=/usr \
        -DEXTERNALS_DOWNLOAD_DIR=$DOWNLOAD_DIR
 
 # Low level libraries and Qt5 dependencies
 # NOTE: The order to compile each component here is very important.
 
 cmake3 --build . --config RelWithDebInfo --target ext_jpeg       -- -j$CPU_CORES
 cmake3 --build . --config RelWithDebInfo --target ext_jasper     -- -j$CPU_CORES
 cmake3 --build . --config RelWithDebInfo --target ext_png        -- -j$CPU_CORES
 cmake3 --build . --config RelWithDebInfo --target ext_tiff       -- -j$CPU_CORES
 cmake3 --build . --config RelWithDebInfo --target ext_qt         -- -j$CPU_CORES
 cmake3 --build . --config RelWithDebInfo --target ext_libgphoto2 -- -j$CPU_CORES
 cmake3 --build . --config RelWithDebInfo --target ext_sane       -- -j$CPU_CORES
 cmake3 --build . --config RelWithDebInfo --target ext_boost      -- -j$CPU_CORES
 cmake3 --build . --config RelWithDebInfo --target ext_opencv     -- -j$CPU_CORES
 cmake3 --build . --config RelWithDebInfo --target ext_lensfun    -- -j$CPU_CORES
 cmake3 --build . --config RelWithDebInfo --target ext_exiv2      -- -j$CPU_CORES
 cmake3 --build . --config RelWithDebInfo --target ext_ffmpeg     -- -j$CPU_CORES
 cmake3 --build . --config RelWithDebInfo --target ext_qtav       -- -j$CPU_CORES
 
 #################################################################################################
 
 TerminateScript