Locally uploaded images does not have thumbnails in Media libraries

[fgrzadkowski]

When I run Wordpress on GAE standard locally on dev_appserver.py, then uploading images doesn't work:

1. they don't have proper thumbnails in Media library
2. they don't show up in posts when included

[ran-dall]

@fgrzadkowski I don't know if you ever found a way to deal with this, but this was happening to me when I didn't have the right permissions on the service account. You have to add Read and Write Permission on the service account otherwise it wouldn't load correctly. You can read more details on my issue #61

[deanscarff]

If folks are seeing full-size images upload to GCS successfully but the thumbnails never appear (both locally and on production GAE), it may be due to #71.