run animations in microtask

packages/svelte/src/internal/client/dom/elements/transitions.js

@@ -303,13 +303,13 @@ function animate(element, options, counterpart, t2, callback) {
 		};
 	}
 
-	var { delay = 0, duration, css, tick, easing = linear } = options;
+	const { delay = 0, css, tick, easing = linear } = options;
 
 	var start = raf.now() + delay;
 	var t1 = counterpart?.t(start) ?? 1 - t2;
 	var delta = t2 - t1;
 
-	duration *= Math.abs(delta);
+	var duration = options.duration * Math.abs(delta);
 	var end = start + duration;
 
 	/** @type {Animation} */
@@ -319,6 +319,7 @@ function animate(element, options, counterpart, t2, callback) {
 	var task;
 
 	if (css) {
+		queue_micro_task(() => {
 			// WAAPI
 			var keyframes = [];
 			var n = Math.ceil(duration / (1000 / 60)); // `n` must be an integer, or we risk missing the `t2` value
@@ -365,6 +366,7 @@ function animate(element, options, counterpart, t2, callback) {
 						throw e;
 					}
 				});
+		});
 	} else {
 		// Timer
 		if (t1 === 0) {