diff --git a/.github/workflows/CreateRelease.yml b/.github/workflows/CreateRelease.yml
index 31c439eae..5928d8047 100644
--- a/.github/workflows/CreateRelease.yml
+++ b/.github/workflows/CreateRelease.yml
@@ -9,6 +9,8 @@ on:
         required: true
         default: 'YYYY.MM'
 
+env:
+  QT_VERSION: 5.15.2
 
 jobs:
   update_ml_version:
@@ -39,8 +41,17 @@ jobs:
       with:
         ref: main
         submodules: recursive
+    - name: Cache Qt
+      id: cache-qt
+      uses: actions/cache@v1
+      with:
+        path: ../Qt
+        key: ${{ runner.os }}-QtCache-${{ env.QT_VERSION }}
     - name: Install Qt
       uses: jurplel/install-qt-action@v2
+      with:
+        path: ../Qt
+        key: ${{ runner.os }}-QtCache-${{ env.QT_VERSION }}
     - name: Install dependencies
       run: |
         bash scripts/${{ runner.os }}/0_setup_env_ubuntu.sh --dont_install_qt --dowload_cgal_and_boost_src
@@ -91,8 +102,17 @@ jobs:
       run: |
         brew install libomp cgal xerces-c
         npm install -g appdmg
+    - name: Cache Qt
+      id: cache-qt
+      uses: actions/cache@v1
+      with:
+        path: ../Qt
+        key: ${{ runner.os }}-QtCache-${{ env.QT_VERSION }}
     - name: Install Qt
       uses: jurplel/install-qt-action@v2
+      with:
+        path: ../Qt
+        key: ${{ runner.os }}-QtCache-${{ env.QT_VERSION }}
     - name: Setup env variables
       id: envs
       shell: bash
@@ -158,8 +178,17 @@ jobs:
         submodules: recursive
     - name: Setup MSVC
       uses: ilammy/msvc-dev-cmd@v1
+    - name: Cache Qt
+      id: cache-qt
+      uses: actions/cache@v1
+      with:
+        path: ../Qt
+        key: ${{ runner.os }}-QtCache-${{ env.QT_VERSION }}
     - name: Install Qt
       uses: jurplel/install-qt-action@v2
+      with:
+        path: ../Qt
+        key: ${{ runner.os }}-QtCache-${{ env.QT_VERSION }}
     - name: Setup env variables
       shell: bash
       id: envs
@@ -172,7 +201,7 @@ jobs:
         echo "VCINSTALLDIR=C:\Program Files (x86)\Microsoft Visual Studio\2022\Enterprise\VC" >> $GITHUB_ENV
     - name: Install wget
       run: |
-        $env:PATH = "C:\msys64\mingw64\bin;C:\msys64\usr\bin"
+        $env:PATH = "${{ env.PATH }};C:\msys64\mingw64\bin;C:\msys64\usr\bin"
         pacman.exe -S --noconfirm --noprogressbar wget unzip
     - name: Set Certificate
       run: |
@@ -193,7 +222,7 @@ jobs:
     - name: Deploy
       shell: C:\shells\msys2bash.cmd {0}
       run: |
-        bash scripts/${{ runner.os }}/2_deploy.sh
+        bash scripts/${{ runner.os }}/2_deploy.sh -qt=${{ env.Qt5_DIR }}
     - name: NSIS script
       shell: bash
       run: |
diff --git a/.github/workflows/Linux.yml b/.github/workflows/Linux.yml
index 6849c2eda..e6da60092 100644
--- a/.github/workflows/Linux.yml
+++ b/.github/workflows/Linux.yml
@@ -3,6 +3,9 @@ name: Linux
 on:
   [push, pull_request]
 
+env:
+  QT_VERSION: 5.15.2
+
 jobs:
   linux_build:
     name: Build MeshLab (Linux)
@@ -15,8 +18,17 @@ jobs:
     - uses: actions/checkout@v2
       with:
         submodules: recursive
+    - name: Cache Qt
+      id: cache-qt
+      uses: actions/cache@v1
+      with:
+        path: ../Qt
+        key: ${{ runner.os }}-QtCache-${{ env.QT_VERSION }}
     - name: Install Qt
       uses: jurplel/install-qt-action@v2
+      with:
+        cached: ${{ steps.cache-qt.outputs.cache-hit }}
+        version: ${{ env.QT_VERSION }}
     - name: Install dependencies
       run: |
         bash scripts/${{ runner.os }}/0_setup_env_ubuntu.sh --dont_install_qt --dowload_cgal_and_boost_src
diff --git a/.github/workflows/MacOS.yml b/.github/workflows/MacOS.yml
index b5eecbcea..3760fe208 100644
--- a/.github/workflows/MacOS.yml
+++ b/.github/workflows/MacOS.yml
@@ -3,6 +3,9 @@ name: MacOS
 on:
   [push, pull_request]
 
+env:
+  QT_VERSION: 5.15.2
+
 jobs:
   macos_build:
     name: Build MeshLab (MacOS)
@@ -19,8 +22,17 @@ jobs:
       run: |
         brew install libomp cgal xerces-c
         npm install -g appdmg
+    - name: Cache Qt
+      id: cache-qt
+      uses: actions/cache@v1
+      with:
+        path: ../Qt
+        key: ${{ runner.os }}-QtCache-${{ env.QT_VERSION }}
     - name: Install Qt
       uses: jurplel/install-qt-action@v2
+      with:
+        cached: ${{ steps.cache-qt.outputs.cache-hit }}
+        version: ${{ env.QT_VERSION }}
     - name: Setup env variables
       id: envs
       shell: bash
diff --git a/.github/workflows/Windows.yml b/.github/workflows/Windows.yml
index 7a2ba585d..2bcb8ca68 100644
--- a/.github/workflows/Windows.yml
+++ b/.github/workflows/Windows.yml
@@ -2,6 +2,9 @@ name: Windows
 
 on: [push, pull_request]
 
+env:
+  QT_VERSION: 5.15.2
+
 jobs:
   windows_build:
     name: Build MeshLab (Windows)
@@ -16,8 +19,17 @@ jobs:
         submodules: recursive
     - name: Setup MSVC
       uses: ilammy/msvc-dev-cmd@v1
+    - name: Cache Qt
+      id: cache-qt
+      uses: actions/cache@v1
+      with:
+        path: ../Qt
+        key: ${{ runner.os }}-QtCache-${{ env.QT_VERSION }}
     - name: Install Qt
       uses: jurplel/install-qt-action@v2
+      with:
+        cached: ${{ steps.cache-qt.outputs.cache-hit }}
+        version: ${{ env.QT_VERSION }}
     - name: Setup env variables
       shell: bash
       id: envs
@@ -30,7 +42,7 @@ jobs:
         echo "VCINSTALLDIR=C:\Program Files (x86)\Microsoft Visual Studio\2022\Enterprise\VC" >> $GITHUB_ENV
     - name: Install wget
       run: |
-        $env:PATH = "C:\msys64\mingw64\bin;C:\msys64\usr\bin"
+        $env:PATH = "${{ env.PATH }};C:\msys64\mingw64\bin;C:\msys64\usr\bin"
         pacman.exe -S --noconfirm --noprogressbar wget unzip
     - name: Download external libraries
       shell: C:\shells\msys2bash.cmd {0}
@@ -43,7 +55,7 @@ jobs:
     - name: Deploy
       shell: C:\shells\msys2bash.cmd {0}
       run: |
-        bash scripts/${{ runner.os }}/2_deploy.sh
+        bash scripts/${{ runner.os }}/2_deploy.sh -qt=${{ env.Qt5_DIR }}
     - name: NSIS script
       shell: bash
       run: |
diff --git a/scripts/Windows/1_build.sh b/scripts/Windows/1_build.sh
index 249171a32..ea3269209 100644
--- a/scripts/Windows/1_build.sh
+++ b/scripts/Windows/1_build.sh
@@ -18,6 +18,7 @@ BUILD_PATH=$SOURCE_PATH/../build
 INSTALL_PATH=$SOURCE_PATH/../install
 DOUBLE_PRECISION_OPTION=""
 NIGHTLY_OPTION=""
+QT_DIR=""
 
 #check parameters
 for i in "$@"
@@ -39,6 +40,10 @@ case $i in
         NIGHTLY_OPTION="-DMESHLAB_IS_NIGHTLY_VERSION=ON"
         shift # past argument=value
         ;;
+    -qt=*|--qt_dir=*)
+        QT_DIR=${i#*=}
+        shift # past argument=value
+        ;;
     *)
         # unknown option
         ;;
@@ -61,6 +66,11 @@ BUILD_PATH=$(realpath $BUILD_PATH)
 INSTALL_PATH=$(realpath $INSTALL_PATH)
 
 cd $BUILD_PATH
+if [ ! -z "$QT_DIR" ]
+then
+    export Qt5_DIR=$QT_DIR
+fi
+
 cmake -GNinja -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=$INSTALL_PATH $DOUBLE_PRECISION_OPTION $NIGHTLY_OPTION $SOURCE_PATH
 ninja
 ninja install
diff --git a/scripts/Windows/2_deploy.sh b/scripts/Windows/2_deploy.sh
index 2dced9b45..8cd70eea3 100644
--- a/scripts/Windows/2_deploy.sh
+++ b/scripts/Windows/2_deploy.sh
@@ -9,6 +9,7 @@
 SCRIPTS_PATH="$(dirname "$(realpath "$0")")"
 RESOURCES_PATH=$SCRIPTS_PATH/../../resources
 INSTALL_PATH=$SCRIPTS_PATH/../../install
+QT_DIR=""
 
 #checking for parameters
 for i in "$@"
@@ -18,15 +19,19 @@ case $i in
         INSTALL_PATH="${i#*=}"
         shift # past argument=value
         ;;
+    -qt=*|--qt_dir=*)
+        QT_DIR=${i#*=}/bin/
+        shift # past argument=value
+        ;;
     *)
         # unknown option
         ;;
 esac
 done
 
-windeployqt $INSTALL_PATH/meshlab.exe
+${QT_DIR}windeployqt $INSTALL_PATH/meshlab.exe
 
-windeployqt $INSTALL_PATH/plugins/filter_sketchfab.dll --libdir $INSTALL_PATH/
+${QT_DIR}windeployqt $INSTALL_PATH/plugins/filter_sketchfab.dll --libdir $INSTALL_PATH/
 
 mv $INSTALL_PATH/lib/meshlab/IFX* $INSTALL_PATH
 cp $INSTALL_PATH/IFXCoreStatic.lib $INSTALL_PATH/lib/meshlab/
@@ -38,6 +43,3 @@ then
     echo "Downloading vc_redist because it was missing..."
     wget https://aka.ms/vs/17/release/vc_redist.x64.exe --output-document=$INSTALL_PATH/vc_redist.x64.exe
 fi
-
-#at this point, distrib folder contains all the files necessary to execute meshlab
-echo "$INSTALL_PATH is now a self contained meshlab application"
diff --git a/scripts/macOS/1_build.sh b/scripts/macOS/1_build.sh
index 12f1164fa..f205775df 100644
--- a/scripts/macOS/1_build.sh
+++ b/scripts/macOS/1_build.sh
@@ -20,6 +20,7 @@ INSTALL_PATH=$SOURCE_PATH/../install
 CORES="-j4"
 DOUBLE_PRECISION_OPTION=""
 NIGHTLY_OPTION=""
+QT_DIR=""
 
 #check parameters
 for i in "$@"
@@ -45,6 +46,10 @@ case $i in
         NIGHTLY_OPTION="-DMESHLAB_IS_NIGHTLY_VERSION=ON"
         shift # past argument=value
         ;;
+    -qt=*|--qt_dir=*)
+        QT_DIR=${i#*=}
+        shift # past argument=value
+        ;;
     *)
         # unknown option
         ;;
diff --git a/scripts/macOS/2_deploy.sh b/scripts/macOS/2_deploy.sh
index 273a9a1b6..818e49fe9 100755
--- a/scripts/macOS/2_deploy.sh
+++ b/scripts/macOS/2_deploy.sh
@@ -11,8 +11,9 @@
 # After running this script, $INSTALL_PATH/meshlab.app will be a portable meshlab application.
 
 SCRIPTS_PATH=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )
+
 INSTALL_PATH=$SCRIPTS_PATH/../../install
-APPNAME="meshlab.app"
+QT_DIR=""
 
 #checking for parameters
 for i in "$@"
@@ -22,29 +23,17 @@ case $i in
         INSTALL_PATH="${i#*=}"
         shift # past argument=value
         ;;
+    -qt=*|--qt_dir=*)
+        QT_DIR=${i#*=}/bin/
+        shift # past argument=value
+        ;;
     *)
         # unknown option
         ;;
 esac
 done
 
-echo "Hopefully I should find " $INSTALL_PATH/$APPNAME
-
-if ! [ -e $INSTALL_PATH/$APPNAME -a -d $INSTALL_PATH/$APPNAME ]
-then
-    echo "Started in the wrong dir: I have not found the meshlab.app"
-    exit -1
-fi
-
-
-if [ -e $QTDIR/bin/macdeployqt ]
-then
-    MACDEPLOYQT_EXE=$QTDIR/bin/macdeployqt
-else
-    MACDEPLOYQT_EXE=macdeployqt
-fi
-
-${MACDEPLOYQT_EXE} $INSTALL_PATH/$APPNAME \
+${QT_DIR}macdeployqt $INSTALL_PATH/$APPNAME \
     -executable=$INSTALL_PATH/$APPNAME/Contents/PlugIns/libedit_align.so \
     -executable=$INSTALL_PATH/$APPNAME/Contents/PlugIns/libfilter_csg.so \
     -executable=$INSTALL_PATH/$APPNAME/Contents/PlugIns/libfilter_isoparametrization.so \