Dropshare 4.9 and later
Sometimes you have the need to validate that a file has not been modified after you've uploaded it with Dropshare, both to protect you and the recipients. This can be achieved with using Integrity Hashes.
To enable them, open the Upload preferences and turn on "Append Integrity Hash to URL". Dropshare will then append a SHA2-256 checksum to each upload URL, e.g. https://s3.amazon.com/my-bucket/1.jpg#c99d8732b3a1a62caaf5d36aeead4562da6d8109(...)
This hash does no harm and does not interfere with any storage provider's functionality.
To validate the integrity of a file, download it and use the program shasum installed on your Mac to re-calculate the integrity hash of it.
Open Terminal.app and type e.g.:
shasum -a 256 ~/Downloads/1.jpg
The program will then print the calculated integrity hash sum of the file. If it matches the one which has been appended to the URL before, you can be safe the file has not been modified meanwhile.