Make it optional to pass the filename when transferring a file
A file transfer passes the original filename to the recipient. While this is mostly practical, it could sometimes imply a privacy breach. So it should be optional to pass the filename. It could be a setting (opt-in) to not confuse users who do not care.
This can relate to #812 (moved) which if being implemented, such dialog could also offer the ability to change or unset the filename. If the filename is unset, the recipient would then be forced to choose a filename before exporting (saving) the file.