An effort is underway to examine how feed publishers and feed consumers are handling the lack of clarity in the RSS 2.0 specification about whether an item can contain more than one enclosure. The RSS Best Practices Profile recommends that a feed item should contain no more than one enclosure "for best support in the widest number of aggregators," advice worth testing against current usage.

The artisanal small-batch blogging service Micro.blog is a platform for sharing short posts like Twitter, but in a way designed to be less viral, more low key and less prone to provocation, attention seeking and clout chasing. There are no follower counts, public likes or trending topics. Founder Manton Reese explained why in his book Indie Microblogging:

Big social networks like Instagram are designed to amplify accounts that gain traction, whether they are fake or not.

Micro.blog limits search and avoids public likes and reposts so that the snowball starts small and stays small. Instead of going viral and becoming a major problem, fake accounts can be spotted early and shut down if necessary.

Since being funded by a Kickstarter campaign in 2017 that hit its goal in one day, Micro.blog has attracted a dedicated following. One of the options available to premium subscribers is to host a podcast. An audio button appears below the post editing window to choose a media file.

Micro.blog sites have a primary RSS feed and a separate podcast feed. The latter contains enclosure elements. Because the Micro.blog editing window does not allow more than one podcast to be added to a post, the RSS item for a post contains only one enclosure:

<item>
  <title>RSS Enclosure Test</title>
  <link>https://rcade.micro.blog/2023/07/02/rss-enclosure-test.html</link>
  <pubDate>Sun, 02 Jul 2023 21:39:52 -0400</pubDate>
  <guid isPermaLink="true">https://rcade.micro.blog/2023/07/02/rss-enclosure-test.html</guid>
  <description><p>I’m trying out Micro.blog’s support for podcasting to see how it handles enclosures in RSS feeds. This MP3 was released by David Byrne under Creative Commons Sampling Plus:</p> <p><a href="https://creativecommons.org/licenses/sampling+/1.0/.">creativecommons.org/licenses/…</a></p> <audio controls="controls" src="https://cdn.uploads.micro.blog/67258/2023/my-fair-lady-david-byrne.mp3" preload="metadata"> </description>
  <itunes:subtitle><p>I’m trying out Micro.blog’s support for podcasting to see how it handles enclosures in RSS feeds. This MP3 was released by David Byrne under Creative Commons Sampling Plus:</p> <p><a href="https://creativecommons.org/licenses/sampling+/1.0/.">creativecommons.org/licenses/…</a></p> <audio controls="controls" src="https://cdn.uploads.micro.blog/67258/2023/my-fair-lady-david-byrne.mp3" preload="metadata"> </itunes:subtitle>
  <itunes:summary><p>I’m trying out Micro.blog’s support for podcasting to see how it handles enclosures in RSS feeds. This MP3 was released by David Byrne under Creative Commons Sampling Plus:</p> <p><a href="https://creativecommons.org/licenses/sampling+/1.0/.">creativecommons.org/licenses/…</a></p> <audio controls="controls" src="https://cdn.uploads.micro.blog/67258/2023/my-fair-lady-david-byrne.mp3" preload="metadata"> </itunes:summary>
  <enclosure url="https://rcade.micro.blog/uploads/2023/my-fair-lady-david-byrne.mp3" type="audio/mpeg" length="3394751"/>   <itunes:duration>212</itunes:duration>
</item>

Micro.blog's commitment to being small extends to podcasts, where its Wavelength app for iPhone can be used to record, edit and publish a short-form podcast.