You're very welcome!
Zitat
The latest google photo app no longer allows a download to phone
Oh then this could be the cause of the problem!
Your Browser is always the layer between the data on your device and the website that gets displayed. That's surely a good thing because the browser can control what gets transfered and what not, so no website can take more data from your device during for example an upload than you allow it to.
This means that your browser doesn't do a direct connection between your Apps or Cloud Services and a Website Upload Form itself: Normally the data from a Cloud Storage gets loaded into a local cache first and from there it gets uploaded to the website from your browser. If Google Photos now disallows the download it could happen that the browser still "thinks" it is possible (that's why it still shows you this source) but if it requests the image from Google Photos there is basically a 0-Byte-File send to the Webform - or in other words: There is no picture there that could be uploaded.
Normally I'd say this is a bug in the browser or app then, but if they kicked out the download function out of their app completely it sounds to me that this behaviour not to give out any photos is intentional. Even though that's a bit of a bummer for the end user to have all pictures locked inside a walled garden.
Sincerely,
Chris