It is often unclear if this should be reported to H5P or Moodle, but will start here.

Problem: Using a keyboard for navigation, when an H5P is embedded on another activity type (such as an accordion on a lesson), "Skip to main content" appears in the embedded H5P. This is a duplication of the intended behavior where "Skip to main content" appears when initially starting keyboard navigation.

Steps to Reproduce:

1. Create an H5P content item in the content bank
2. Use the Atto or Tiny editor to embed the H5P content item on a page, lesson, or similar activity type
3. Save the content item, and navigate the page with tab
4. Notice that "Skip to main content" appears inside the iframe for the H5P

We have confirmed this happens on other themes other than what is in this image.