So I finished backing up my SSD a few hours ago and when I went to make sure that all of my files got backed up, I realised that there was a huge difference on the file size. So, while the files on my SSD are 966GB, the backup on Dropbox is 807GB. This is a huge difference and I need to empty my SSD as soon as possible. I dont know if everything is backed up, but I can see that there's even a difference in the size of a single photo. Its about 1mb less on the backup of dropbox compared to the original file on my SSD.