diff --git a/mautrix_telegram/portal.py b/mautrix_telegram/portal.py
index 6c3daa4d..e0e9622a 100644
--- a/mautrix_telegram/portal.py
+++ b/mautrix_telegram/portal.py
@@ -940,7 +940,7 @@ class Portal:
         for attr in attributes:
             if isinstance(attr, DocumentAttributeFilename):
                 attrs["name"] = attrs["name"] or attr.file_name
-                attrs["mime_type"] = mimetypes.guess_type(attr.file_name)
+                attrs["mime_type"], _ = mimetypes.guess_type(attr.file_name)
             elif isinstance(attr, DocumentAttributeSticker):
                 attrs["is_sticker"] = True
                 attrs["sticker_alt"] = attr.alt
diff --git a/setup.py b/setup.py
index 190a9f90..ea50e271 100644
--- a/setup.py
+++ b/setup.py
@@ -26,7 +26,7 @@ setuptools.setup(
 
     install_requires=[
         "aiohttp>=3.0.1,<4",
-        "mautrix-appservice>=0.1.3,<0.2.0",
+        "mautrix-appservice>=0.1.4,<0.2.0",
         "SQLAlchemy>=1.2.3,<2",
         "alembic>=0.9.8,<0.10",
         "Markdown>=2.6.11,<3",