Hi, I got this Debian bug report: "xdg-email accepts an initial body with the --body command-line option. However, with a sufficiently long email, this could run into command-line length limits. Thus, xdg-email needs an option to accept the body on standard input instead. - Josh Triplett" https://bugs.debian.org/427728
There is no general way to pass stdin to the e-mail client that eventualy gets loaded. I agree that the command line approach imposes undesired restrictions but until the developers of Linux e-mail clients agree on better standards for invoking these clients (through a standard dbus interface for e-mail clients for example) there is little that can be done.
But is this a reason for xdg-email not supporting stdin? Can't it accept input on stdin, but return an error if it is too long? That way the interface will be ready for when the e-mail clients are.
Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.