Also sanitize leading .

That way hidden files that are uploaded will be "de-hidden".

Note that NO "de-hiding" of existing files will take place!

src/octoprint/filemanager/storage.py

@@ -624,7 +624,11 @@ class LocalFileStorage(StorageInterface):
 		if "/" in name or "\\" in name:
 			raise ValueError("name must not contain / or \\")
 
-		return self._slugify(name).replace(" ", "_")
+		result = self._slugify(name).replace(" ", "_")
+		if result.startswith("."):
+			# hidden files under *nix
+			result = result[1:]
+		return result
 
 	def sanitize_path(self, path):
 		"""