My gif header works perfectly fine on the tumblr app on my ipad, but doesn't work on safari or on my computer, is there any way to fix this?

My gif header works perfectly fine on the tumblr app on my ipad, but doesn't work on safari or on my computer, is there any way to fix this?

Read more: My gif header works perfectly fine on the tumblr app on my ipad, but doesn't work on safari or on my computer, is there any way to fix this?