Set_Post_Thumbnail_Size Question?

Hello guys.

I have question and why this theme added set_post_thumbnail_size(1200,9999)?

We are building the Lazy Load plugin and if we cropped original image to blurred and cropped image then this 9999 is conflicted and original image proportion is broken. I don’t know why this happen but if we set it set_post_thumbnail_size(1200,0) it’s working good.

That’s the Question…

Thanks.