diff --git a/qfieldsync/gui/cloud_transfer_dialog.py b/qfieldsync/gui/cloud_transfer_dialog.py
index cb99d81e..4e023cac 100644
--- a/qfieldsync/gui/cloud_transfer_dialog.py
+++ b/qfieldsync/gui/cloud_transfer_dialog.py
@@ -28,7 +28,12 @@
 
 from libqfieldsync.layer import LayerSource, SyncAction
 from libqfieldsync.offline_converter import ExportType
-from libqfieldsync.project_checker import ProjectChecker
+from libqfieldsync.project_checker import (
+    Feedback,
+    FeedbackResult,
+    ProjectChecker,
+    ProjectCheckerFeedback,
+)
 from libqfieldsync.utils.file_utils import get_unique_empty_dirname
 from libqfieldsync.utils.qgis import get_qgis_files_within_dir
 from qgis.core import Qgis, QgsApplication, QgsProject, QgsProviderRegistry
@@ -56,7 +61,7 @@
 from qfieldsync.core.preferences import Preferences
 from qfieldsync.gui.checker_feedback_table import CheckerFeedbackTable
 from qfieldsync.gui.storage_widget import StorageWidget
-from qfieldsync.utils.file_utils import filesizeformat10
+from qfieldsync.utils.file_utils import filesizeformat10, open_qgis_file
 from qfieldsync.utils.qt_utils import make_folder_selector, make_icon, make_pixmap
 
 CloudTransferDialogUi, _ = loadUiType(
@@ -267,6 +272,33 @@ def show_project_compatibility_page(self):
             if self.cloud_project and self.cloud_project.is_current_qgis_project:
                 checker = ProjectChecker(QgsProject.instance())
                 feedback = checker.check(ExportType.Cloud)
+            elif (
+                self.cloud_project
+                and self.cloud_project.local_project_file
+                and self.cloud_project.local_project_file.local_path
+            ):
+                feedback = ProjectCheckerFeedback()
+                is_qgis_version_4 = False
+                with open_qgis_file(
+                    self.cloud_project.local_project_file.local_path
+                ) as f:
+                    for _i in range(2):
+                        if 'version="4.' in str(f.readline().strip()):
+                            is_qgis_version_4 = True
+                            break
+
+                if is_qgis_version_4:
+                    feedback.add(
+                        Feedback(
+                            Feedback.Level.ERROR,
+                            FeedbackResult(
+                                self.tr(
+                                    "QFieldCloud does not yet support projects saved using QGIS >= 4.0. "
+                                    "Please configure your projects using QGIS 3.44 until further notice."
+                                )
+                            ),
+                        )
+                    )
 
             if feedback and feedback.count > 0:
                 # check whether the widget has already been added the guard from adding twice due to repeated showEvent signal
diff --git a/qfieldsync/utils/file_utils.py b/qfieldsync/utils/file_utils.py
index 8e20cf8c..d1285f9c 100644
--- a/qfieldsync/utils/file_utils.py
+++ b/qfieldsync/utils/file_utils.py
@@ -24,10 +24,11 @@
 import shutil
 import stat
 import time
+import zipfile
 from collections.abc import Callable
 from enum import Enum
 from pathlib import Path
-from typing import Optional, TypedDict, Union
+from typing import Optional, TextIO, TypedDict, Union
 
 from qgis.PyQt.QtCore import QObject
 
@@ -339,3 +340,15 @@ def filesizeformat10(bytes_: int) -> str:
         value = "-{}".format(value)
 
     return value
+
+
+def open_qgis_file(filename: PathLike) -> TextIO:
+    filename = Path(filename)
+
+    if filename.suffix.lower() == ".qgz":
+        with zipfile.ZipFile(filename, "r") as qgz:
+            return qgz.open(f"{filename.stem}.qgs")
+    elif filename.suffix.lower() == ".qgs":
+        return open(filename)
+
+    return None
diff --git a/requirements.txt b/requirements.txt
index 131d1d8e..085bb8ab 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,2 +1,2 @@
 # NOTE `libqfielsync` version should be defined in the `*.tar.gz` format, not `git+https://` to make `wheel` happy
-libqfieldsync @ https://github.com/opengisch/libqfieldsync/archive/b83bfa46646d218a95202b62e8431354ead3de48.tar.gz
+libqfieldsync @ https://github.com/opengisch/libqfieldsync/archive/ee83e64a8026f80a96031a5d3b3c32d72633af2e.tar.gz