Figma Motion : Gif export problem

Hello Figma,

I use Figma Motion because it’s easy to make a basic motion without export many files.

For the context, i make a 20 seconds timer with animation at the beggining and the end of animation.
The start and end animations each last 1 second with 0.5 seconds of blank before or after.

But i have a mysterious problem, i would like export to GIF because it’s the only format who accept transparent background.
But when i export a 30 seconds motion in GIF ( 1080p / 30fps / x1 / Loop doesn’t matter ) , the GIF last 28 seconds.
And when i see the GIF, i see my timer of 20 seconds is 2 seconds shorter like it’s more speedy than the timeline show.

I test with MP4 ou WEBM, exports last well 30 seconds.
And the antoher GIFs i made with Figma Motion are shorter than MP4 or WEBM export. ( Timeline show 13 secondes, but the export takes 11 seconds. )

Can you fix this problem ? Thank you !

( If I could make a suggestion, it would be to be able to create a key image for text editing, because doing 13 layers to do 2 to 0 and 9 to 0 for the timer is a bit long to do. )

I wish you a good day and goodbye!