I uploaded this animation and tried adding it to this article but the animation did not play despite only being the small thumbnail version (I used the "thumb" parameter).

On the file's pages (Commons and WP) it only displayed: ''Note: Due to technical limitations, thumbnails of high resolution GIF images such as this one will not be animated.'' which was not helpful for solving this problem and I couldn't find any help page with information that helps solving this. If there is a help page for animations please link it here - otherwise the creation of such a page would be needed as well.

In this discussion I learned about the width × height × framerate × seconds < 100 million limit for animations and that apparently currently the short-term solution to this is a making a separate upload with a smaller version.

Could pages please use the downsized / thumbnail version below that limit? Just like with images, pages don't need to use the full-sized .gif when the animation is displayed in a smaller size on it.

I haven't checked if pages really use the largest version of the gif but implementing or improving downsized embeddment of animations would bring benefits of reduced server-load and/or better media-quality and/or better media-load-speed/bandwidth-usage.

• It looks like the smaller versions of the animated .gif file that are automatically rendered (linked at the file on Commons next to "Other resolutions:") are not animated and hence can't be used in pages that embed the animated gif: so the first step would be automatically creating animated downsized versions of the animated gifs (making sure that the downsized versions are animated if the file is an animated gif).
• When the automatic rendering has been adjusted the thumbnail / size-specifications of embedded animated gifs may need to be adjusted as well so that they use the smaller (downsized) renderings instead of the full-sized version.
• Once this has been done, adherence to the mediawiki-limit of $wgMaxAnimatedGifArea=100 million could be automatically implemented for embedments if they exceed that limit: either by e.g. automatically changing the size for it to be the maximum animatedgifarea or by including a downsized render just below this limit in the automatic renderings ("Other resolutions:").

Lastly, it would be nice if one could embed WebM files as animations like gifs with some parameter (so that one does not has to click the play button and the animation automatically plays in a loop). That would be a separate issue though and may or may not be related to this issue.