HEIC image supported or not (docs say yes, but they don't work)?

According to the docs, image/heic images are supported .

However, both the ai studio playground as well as the api reject them in my tests (in the playground: “Images must be in .jpg, .png or .webp format” and in the API: “Provided image is not valid”).

Please advise.

I believe its a documentation mismatch.
We could convert HEIC to a PNG or JPEG before upload as a workaround.
Do file a bug via feedback of AI Studio.