Does this happen with all emojis or only with animated emojis ? Firefox 63+ has support for "@media (prefers-reduced-motion)" to honor system Settings to minimize the amount of non-essential motion. You can create a new Number pref named <b>ui.prefersReducedMotion</b> on the <b>about:config</b> page to show (0) or block (1) some animations. *in Firefox 78+ this includes the location bar breakout *in Firefox 80+ this replaces the tab loading indicator with an hourglass *set the value to 1 if you want to block animations<br>ui.prefersReducedMotion = 1 *set its value to 0 if you want to see animations<br>ui.prefersReducedMotion = 0