An important distinction to make is that between filtered transclusions in wikitext, and filtered attributes for widgets.
In the former, the {{{ filter || template }}} format is supported because the output gets wikified. In the latter, this is not supported as the literal value of the filter is assigned to the attribute, similar to attribute={{!!field}} -- You received this message because you are subscribed to the Google Groups "TiddlyWikiDev" group. To unsubscribe from this group and stop receiving emails from it, send an email to tiddlywikidev+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/tiddlywikidev/e142eb57-cf94-4a59-b299-bb9608745776n%40googlegroups.com.