Exported panorama from Photoshop on Mac fails on Facebook

Thanks @JonathanArias, your suggestion, in tandem with templated images available online to resolve these issues, has provided the answer.

It's as simple as this; the image size needs to be below the maximum thresholds facebook sets (6000 x 3000), AND the equirectangular image has to be 2:1.

I amended my image to 4000 x 2000 pixels and repeated the simple export panorama process - uploaded fine and was recognised instantly by Facebook - a sphere icon appears within the image and they then let you select the "front" view for your thumbnail.

Image size is 3840 by 2160; the image is a still JPEG, taken from an Adobe After Effects video which is in the Media Encoder currently with 22 hours to run (some significant animation and post-production ongoing on that).

Fair comment from JohanEl54 - here's a fuller explanation in case there's a clue in there somewhere.

I was keen to get some shareable output, as this is a bit of a landmark day (this represents months of work toward a new artistic project).

I opened Photoshop. I selected File/Open, browsed to my JPEG, opened it;

then selected 3D/Spherical Panorama/New Panorama Layer from Selected Layer(s)

(This generated a 360 browsable view of my equirectangular image in PhotoShop immediately, so it appeared to be working successfully)

I then selected 3D/Spherical Panorama/Export Panorama; left all settings as defaults (an alert advised that "File must be saved as a copy with this selection", which was fine by me.

I then went to Facebook in my browser, went to upload photos/videos; browsed to my saved file, and uploaded it. There was no comment in Facebook to suggest that the image was a 360 photo, and on browsing the content once published it appeared as a flat file.

My understanding is that it should be as simple as "Export Panorama", then upload as required.I've also tried inserting 360 metadata from a downloaded Exif template and that was also unsuccessful.

maybe the image is larger than what facebook allows? that is the only thing that would stop you from posting an image on facebook. the size of it.

Probably, but if you only tell us "I followed the Adobe tutorials and 3rd party advice online", then it will be impossible for us to say what it is you missed.