diff --git a/dangerzone/container.py b/dangerzone/container.py
index cd7eb8d..14c034d 100644
--- a/dangerzone/container.py
+++ b/dangerzone/container.py
@@ -17,8 +17,8 @@ else:
 
 # Define startupinfo for subprocesses
 if platform.system() == "Windows":
-    startupinfo = subprocess.STARTUPINFO()
-    startupinfo.dwFlags |= subprocess.STARTF_USESHOWWINDOW
+    startupinfo = subprocess.STARTUPINFO()  # type: ignore [attr-defined]
+    startupinfo.dwFlags |= subprocess.STARTF_USESHOWWINDOW  # type: ignore [attr-defined]
 else:
     startupinfo = None
 
diff --git a/dangerzone/global_common.py b/dangerzone/global_common.py
index a979ff9..362de41 100644
--- a/dangerzone/global_common.py
+++ b/dangerzone/global_common.py
@@ -417,7 +417,7 @@ class GlobalCommon(object):
         resource_path = prefix.joinpath(filename)
         return str(resource_path)
 
-    def get_subprocess_startupinfo(self):
+    def get_subprocess_startupinfo(self):  # type: ignore [no-untyped-def]
         if platform.system() == "Windows":
             startupinfo = subprocess.STARTUPINFO()
             startupinfo.dwFlags |= subprocess.STARTF_USESHOWWINDOW