I also would like to know more about the possibility of using new file formats, like jpeg2000 (this is mostly for apple users) and webp (everyone else).
I code static websites too, and I use webpacker to do all the transformations every time I upload to the server. Here the implementation would not be as easy I imagine since it would have to be done by a library on the backend (HubSpot’s side).
Also template would probably need to be updated to support this feature.
But I want to know if this is implemented.