Twitter has today announced that the website will start blocking animated PNG files (or APNGs) from being posted to the social media platform. The company made the announcement via the official Twitter Support handle in a tweet that explained that animated PNG files ignore the company’s safeguards and can cause performance issues on both the Twitter app and a user’s device.

We recently found a bug that lets you add multiple animated images to a Tweet using Animated PNG files. APNGs ignore our safeguards and can cause performance issues for the app and your device. Today we’re fixing the bug which will no longer allow APNGs to animate when Tweeted.

The official Twitter Engineering handle also shed some light on the potential performance pitfalls of using APNGs on Twitter in a tweet.

Using PNGs for animation is difficult. APNGs are orders of magnitude larger than normal preview images. This can mean a slower app, increased memory use and even crashes. These problems make for an unpleasant Twitter experience, and there’s little that can be done to avoid it. https://t.co/IsWwIm6mYz