- Point the client URL at a WOPI-compatible office suite (Collabora Online, OnlyOffice, EuroOffice, …) to let users edit documents in Files. The host override is only needed when the editor reaches this webmail under a different address than the browser does (e.g. Docker networks). The editor must also allow this webmail as a WOPI host. + Point the client URL at a WOPI-compatible office suite (Collabora Online, OnlyOffice, EuroOffice, …) to let users edit documents in Files. The client URL may be an internal address: the browser loads the editor from the address its discovery advertises. The host override is only needed when the editor reaches this webmail under a different address than the browser does (e.g. Docker networks); give the address alone, the webmail's base path is added to it. The editor must also allow this webmail as a WOPI host.