Some users want the assembled HDR JPEG for somewhere other than
Instagram, where the exact 1080x1080/1080x1350/1080x566 match isn't
relevant. A checkbox on the form now lets the whole batch skip that
specific check. The SDR/HDR dimension-match check still always
applies, since that's a technical requirement for the gain map to
align, not an Instagram-specific rule.
Djeex