[alfiedotwtf]

My money is on AVIF. HEIC-based images that are encumbered and non-royalty free don't have a chance on open source platforms

[out_of_protocol]

Adding JpegXL to discussion. For still images it's about the same as AVIF, for high-compression samples AVIF have upper hand, for high-quality samples JpegXL feels better. Also, JpegXL is much faster, simpler, allows progressive encoding