While video autoplay is supported for landing pages ( where a single video is played) It is not supported for embedding on pages. Why you'd ask?
Main Reasons Summery
First here are main reasons pointed out why it is not recommended any why also services such as Netflix, Amazon, YouTube and other do not use autoplay on video overview pages.
Slow Website Loading: Autoplay videos begin downloading and playing immediately when a webpage is visited. This can slow down the overall website loading speed, especially if the video files are large or numerous.
High Data Usage: Videos, especially high-quality ones, use up a lot more data than text or images. This higher data usage can affect the user's data plan and slow down their internet connection.
Processing Power: Videos require more processing power to download and play than loading static content, putting more strain on the user's device and potentially slowing down its performance.
Cache Limitations: Video files are usually too large to be efficiently stored in the browser cache. This means every time a user visits the website, the browser may need to download the video again, leading to slower loading times.
User Experience: Auto-play can be distracting or annoying for users, especially if they are in a quiet environment or the video content isn't immediately relevant to them. It also removes the user's choice in deciding what content they want to engage with.
Conflicts with GDPR: Autoplay videos can potentially conflict with the General Data Protection Regulation (GDPR) and other privacy laws. These regulations require that users consent to data processing activities, and autoplay videos, especially those that track user behavior or contain cookies, could potentially be collecting user data without explicit consent. This is especially important if the video is embedded from a third-party platform that uses tracking cookies.
Browser Cache Limitations
Now, about the browser cache. A browser cache is like a little memory storage in your computer where data from the websites you've visited is stored temporarily. It helps websites load faster when you visit them again because it has some of the site's data already stored and doesn't need to download everything anew.
However, video files are often too big to be efficiently stored in the cache. Also, if a video is auto-playing, the browser may need to keep updating the cached version, which again uses up more data and slows down the loading process. That is why services like YouTube, Vimeo, Amazon or Netflix, to not autoplay videos on result pages - to avoid freezing of browsers and for better user experience.
Alternative Solution
Instead, a good alternative to autoplay videos can be using an animated GIF as a placeholder. GIFs are image files that can be animated, and they're much smaller in size than videos. They don't require as much data or processing power to load, which means they won't slow down the webpage as much. Plus, they can still give visitors a preview or snapshot of the video content. If a visitor is interested, they can click on the GIF to play the full video.
However, do keep in mind that while GIFs are smaller than video files, they are larger than static images. Therefore, it's important to optimize the GIF to ensure it loads quickly and doesn't slow down the website.
By avoiding autoplay videos and using alternatives like GIFs, you can improve the speed of your website and provide a better user experience.