Check https://news.ycombinator.com/item?id=20498454 Dropbox did drop support and bring it back. I use Linux with xfs, so I switched off Dropbox. Even though Dropbox went back on this decision, they did some damage, and probably lost people that haven't come back (like me).

Thanks, I hadn’t been aware that they relaxed the requirements. In my case it doesn’t help me though, as the VPS I’m using is still on ext3.