
X6 can make images too large for Facebook ;-) "Oops" error.
Updated description: "Some X6 360 photos get rejected by Facebook" perhaps.
UPDATE: I have had images 74MB that upload just fine, then ones that are 67MB and 71MB that fail 100% of the time (personal page, group, or business page). I have tried Chrome browser as well. File size may have nothing to do with the failures. These are 15520x7760 images from the X6. I have renamed the two images that fail for me and placed them with the others in case you want to try them (maybe a problem with my Meta account):
Apparently, the 120MP image sometimes is too large for Facebook. I uploaded about ten images and two of them get rejected. I have one at 56MB that works, then one at 67MB that is rejected.
To get them uploaded, I use Graphic Converter (Mac) to compress them down to a smaller file size.
Searching for the largest file Facebook accepts shows me these should work -- but even Facebook's own help does not specifically address 360-degree photos where the width is 2X the height. Perhaps that is part of it.
It gives the annoying "Oops" error.