Yohan Yukiya Seseㆍ사요한・謝雪矢@mgifford Last year, #Flickr said they are studying it. We haven't heard any updates since.
I would suggest using #Pixelfed for your photos since you can upload more than 4 images through it. Or, any other Fediverse software; avoid Mastodon when it comes to images/gallery: (1) you can only upload max 4 images; and (2) anything beyond 4 attachments, Mastodon sends it to the blackhole. It's not a bug, it's by-design, still, it should be “fixed”.
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