Hi Henrik Reer
Greetings & Welcome to the Microsoft Q&A forum! Thank you for sharing your query.
Modern browsers have implemented restrictive autoplay policies. Browsers such as Chrome, Firefox, Safari, and Edge block autoplay for videos with sound by default to prevent annoyance and save data. However, autoplay is permitted for muted videos, as browsers prioritize user experience and data conservation. Thus, while autoplay with sound is generally disabled to minimize disruptions, muted videos are allowed to autoplay because they do not interfere with the user experience or consume unnecessary data. can you please refer these https://developer.chrome.com/blog/autoplay/
I hope this helps you. Thank you.