tony
You can also open in Wordpad and then save. Works at least in XP, don't have 8 or 10 handy to check. Use this trick on other files that some programs create.
I have installed a Generic pain text printer in Windows on the port FILE: I open a given tiddler in a new window and Use the browser print function (Sadly not in TiddlyDesktop) and print to this printer. This way I can name the file output to name.txt name.cmd etc... and save it where I wish.