@palmin I just tries to reproduce the error which so far always occured upon the second call of the x-url-callback. Fortunately, I was not able to reproduce it which is that the server was also started by the second call. However, during both the first and the second call it takes 'working copy' about 10 seconds to return to Pythonista.

This is the call issued: working-copy://x-callback-url/webdav/?cmd=start&key=[KEYREPLACED]&x-success=pythonista%3A%2F%2Fgitsynchista%2Fgitsynchista%3Faction%3Drun%26argv%3DIGNORE_WAKEUP'