Report from the PDF Association Working Group with a lot of practical examples
Since December 2018 some of the world's most trusted PDF accessibility experts work together to create atomic examples of WCAG 2.1 compliant PDF files. We report about the current status. You will get to know the basic concept as well as a lot of practical examples for failing and passing files.
Slides download: https://www.pdfa.org/wp-content/uploads/2020/07/2020-10-21_What-about-an-update-of-the-WCAG-Techniques-for-PDF_AbleDocs_Markus-Erle.pdf