diff --git a/plugins/http-files/src/file_provider.vala b/plugins/http-files/src/file_provider.vala
index 3fa32097..82ccc710 100644
--- a/plugins/http-files/src/file_provider.vala
+++ b/plugins/http-files/src/file_provider.vala
@@ -89,7 +89,9 @@ public class FileProvider : Dino.FileProvider, Object {
                 if (name == "Content-Length") content_length = val;
             });
             file_transfer.mime_type = content_type;
-            file_transfer.size = int.parse(content_length);
+            if (content_length != null) {
+                file_transfer.size = int.parse(content_length);
+            }
         }
     }
 
diff --git a/plugins/omemo/src/file_provider.vala b/plugins/omemo/src/file_provider.vala
index 70e59574..0e11c8f4 100644
--- a/plugins/omemo/src/file_provider.vala
+++ b/plugins/omemo/src/file_provider.vala
@@ -91,7 +91,9 @@ public class FileProvider : Dino.FileProvider, Object {
                     if (name == "Content-Length") content_length = val;
                 });
                 file_transfer.mime_type = content_type;
-                file_transfer.size = int.parse(content_length);
+                if (content_length != null) {
+                    file_transfer.size = int.parse(content_length);
+                }
             } else {
                 warning("HTTP HEAD download status code " + head_message.status_code.to_string());
             }