New format breaks old links

Example is Google, but can be any link on the web

points to https://eic.github.io/tutorial-analysis/01-introduction/index.html
but the new url is https://eic.github.io/tutorial-analysis/01-introduction.html

Search the repository for references to the old /01-introduction/index.html URL and inspect how the corresponding /01-introduction.html URL is produced. Check the affected tutorial links first; the work is done when links using the old format continue to resolve or are updated consistently without breaking the new URL.

Vom Indexierungsmodell aus dem Issue-Text verfasst.