HEIC/HEIF support + dynamic format hint on guest upload 3.91.0-beta.0 (2026-07-18) Features uploads: HEIC/HEIF support + dynamic format hint on guest upload (#821) (ee9d2f7) Bug Fixes gallery: serve JPEG preview for non-displayable originals in lightbox (codex review of #832) (808d305) uploads: register HEIC/HEIF with the file validator + fix admin format hint (codex review of #832) (c9b64d9)