What's the correct syntax for combining RSS feeds using the RSS plugin? The PluginRSS page says at one point "You can also combine feeds by indicating 1+2, or 1+2+3 to add feeds together...", and later in the parameter table it says "list of IDs separated by comma".
The first two just display the first feed, and the last one just displays the last feed.
Yes, "show publish date" is enabled for all feeds.
Tiki version is 2.0.