Twitter has blocked the use of animated PNGs on its platform after trolls used them to attack people with epilepsy.
Last month Twitter trolls took over hashtags and mentions used by the Epilepsy Foundation, sending flashing animated PNGs that could induce seizures. The organization has filed criminal complaints. This isn’t the first time either. In 2016 an an attacker tweeted a strobing GIF at Vanity Fair editor Kurt Eichenwald, who has epilepsy, causing him to have a seizure.
You’ll still be able to add animations to your tweets, but you’ll have to use GIFs. As Twitter mentioned, animated PNGs were able to bypass the site’s autoplay features, which made them an easy format to abuse.