Ed, turns out you're right; the example <https://tiddlywiki.com/#WidgetMessage%3A%20tm-new-tiddler> does propose tagging the template with a particular tag. Instead what you do is this:
<$button> <$action-sendmessage $message="tm-new-tiddler" $param="TaskTemplate" tags="mytag"/> New Tiddler </$button> <:-) -- You received this message because you are subscribed to the Google Groups "TiddlyWiki" group. To unsubscribe from this group and stop receiving emails from it, send an email to tiddlywiki+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/tiddlywiki/f44084a8-0bf3-48c2-ad6a-4510511c29a3%40googlegroups.com.
