Uploading videos to Facebook post

jayscout wrote: Where does Facebook take the video from - the device or icloud

If you use iCloud to synchronize your Photos with iCloud.com and other devices, then the pictures at iCloud.com and those on your iPhone are identical. If you use "Optimize Storage" for Photos on your iPhone, then it may store smaller images on the phone to make more room, but they're all the same pictures. When you need larger versions, for editing or zooming in, etc.., the iPhone grabs them from iCloud.com.

Things that you do with pictures on your phone are all done with the files that are actually on your phone. Sometimes, if Optimize is engaged, and you need a larger sized file, the phone will have to wait a bit for a the full picture to be loaded from iCloud, but then it works only with the image on the phone, itself.

Is this what you needed?