diff --git a/.github/ci_images/bionic_builder.dockerfile b/.github/ci_images/bionic_builder.dockerfile
index a53fc59..c1e76f6 100644
--- a/.github/ci_images/bionic_builder.dockerfile
+++ b/.github/ci_images/bionic_builder.dockerfile
@@ -38,4 +38,8 @@ USER runner
 WORKDIR /home/runner
 ENV PATH /home/runner/.local/bin:$PATH
 
-RUN echo "source /opt/qt515/bin/qt515-env.sh" >> /home/runner/.bashrc
+# Set qt515 environment (the equivalent of "source /opt/qt515/bin/qt515-env.sh")
+# RUN echo "source /opt/qt515/bin/qt515-env.sh" >> /home/runner/.bashrc
+ENV PATH=/opt/qt515/bin:$PATH \
+    LD_LIBRARY_PATH=/opt/qt515/lib/x86_64-linux-gnu:/opt/qt515/lib:$LD_LIBRARY_PATH \
+    PKG_CONFIG_PATH=/opt/qt515/lib/pkgconfig:$PKG_CONFIG_PATH
diff --git a/appveyor/package_kiwix-desktop.sh b/appveyor/package_kiwix-desktop.sh
index 3a68bdd..48cbbbd 100644
--- a/appveyor/package_kiwix-desktop.sh
+++ b/appveyor/package_kiwix-desktop.sh
@@ -22,7 +22,7 @@ then
   mkdir -p KIWIX_ARCHIVES_DIR
 
   cp /c/projects/kiwix-build/kiwix-desktop/Release/kiwix-desktop.exe $KIWIX_DIR
-/c/Qt/5.12/msvc2017_64/bin/windeployqt --compiler-runtime $KIWIX_DIR
+/c/Qt/5.15/msvc2019_64/bin/windeployqt --compiler-runtime $KIWIX_DIR
 
   cp $MINGW64_EXTRA_DIR/aria2c.exe $KIWIX_DIR
   cp $MINGW64_EXTRA_DIR/bin/*.dll $KIWIX_DIR
diff --git a/kiwixbuild/dependencies/flatpak.py b/kiwixbuild/dependencies/flatpak.py
index b64fb5b..d4764ec 100644
--- a/kiwixbuild/dependencies/flatpak.py
+++ b/kiwixbuild/dependencies/flatpak.py
@@ -35,3 +35,34 @@ class org_kde(Dependency):
             self.command('setup_remote', self._setup_remote)
             self.command('install_sdk', self._install_sdk)
 
+
+class org_kde(Dependency):
+    neutral = False
+    name = 'io.qt.qtwebengine'
+
+    Source = NoopSource
+
+    class Builder(Builder):
+        def _setup_remote(self, context):
+            command = "flatpak --user remote-add --if-not-exists {remote_name} {remote_url}"
+            command = command.format(
+                remote_name = 'flathub',
+                remote_url = 'https://flathub.org/repo/flathub.flatpakrepo'
+            )
+            env = self.buildEnv.get_env(cross_comp_flags=False, cross_compilers=False, cross_path=False)
+            run_command(command, self.buildEnv.build_dir, context, env=env)
+
+        def _install_sdk(self, context):
+            command = "flatpak --user install -y {remote_name} {name}.BaseApp//{version}"
+            command = command.format(
+                remote_name = 'flathub',
+                name = self.target.name,
+                version = self.target.version()
+            )
+            env = self.buildEnv.get_env(cross_comp_flags=False, cross_compilers=False, cross_path=False)
+            run_command(command, self.buildEnv.build_dir, context, env=env)
+
+        def build(self):
+            self.command('setup_remote', self._setup_remote)
+            self.command('install_sdk', self._install_sdk)
+
diff --git a/kiwixbuild/platforms/flatpak.py b/kiwixbuild/platforms/flatpak.py
index 81ad37a..4cd8342 100644
--- a/kiwixbuild/platforms/flatpak.py
+++ b/kiwixbuild/platforms/flatpak.py
@@ -5,7 +5,7 @@ class FlatpakPlatformInfo(PlatformInfo):
     name = 'flatpak'
     build = 'flatpak'
     static = ''
-    toolchain_names = ['org.kde']
+    toolchain_names = ['org.kde', 'io.qt.qtwebengine']
     compatible_hosts = ['debian', 'fedora']
 
     def __str__(self):
diff --git a/kiwixbuild/versions.py b/kiwixbuild/versions.py
index 382cd97..fe5eba1 100644
--- a/kiwixbuild/versions.py
+++ b/kiwixbuild/versions.py
@@ -60,5 +60,6 @@ base_deps_versions = {
   'qt' : '5.10.1',
   'qtwebengine' : '5.10.1',
   'org.kde' : '5.15',
+  'io.qt.qtwebengine' : '5.15',
   'zim-testing-suite': '0.3',
 }