RSS (and maybe Atom?) syndication feeds for articles do not consistently output images and text on Tiki.org?

I'm not sure if this is just an issue with how the Tiki.org instance is configured, or how these particular posts are configured, or if it's a legit bug in the way Tiki outputs its RSS... but if you add https://tiki.org/tiki-articles_rss.php?ver=5 to a feed reader such as Liferea or Jan Lukas Gernert's FeedReader / NewsFlash (all of which are available on Linux), you will get incomplete contents displayed for some of the articles, namely:

• https://tiki.org/article495-We-Are-Celebrating-20-Years-of-Tiki only shows the image (not the interview text), or sometimes (in FeedReader) only a broken image
• https://tiki.org/article497-Biggest-Tiki-Release-Ever-Tiki-25 shows the text but not the image, and the "read on" part (assuming there's metadata to separate an abstract from the rest of the article) does have hyperlinking to the full article.
  • I'm unsure if the "read on" abstract separation is something that is standardized and if there's a way to indicate to feed readers that there is an extra part to be linked to, rather than needing the writer to manually link (which would be hard to accomplish).

See attached screenshots of how it renders in Liferea and FeedReader.

1. FeedReader's Rendering Of Article On 25.0 Release
2. FeedReader's Rendering Of Article On 20 Years Celebration
3. Liferea's Rendering Of Article On 25.0 Release
4. Liferea's Rendering Of Article On 20 Years Celebration