Thanks for your replies! Does anyone know where temporary files on Android for Opera mini are stored and could I recover bookmarks this way? Would the phone have to be rooted to recover these files?
I've done a lot of searches on the Internet for solutions and there's some software that claims that lost Opera data can be restored using a PC and connecting your phone by usb but I'm a bit skeptical...
I'm also confused by what happened with the sync itself. Before cleaning the cache, I signed out of my Opera account and still haven't signed back in, but all of the bookmarks were gone online after clearing the cache. This really makes no sense to me because I thought you'd have to be signed into the account in order for them to sync. I signed out of my account just in case something went wrong and thought that I could sync the bookmarks and folders back to my phone... It seems that there should be a way to recover the bookmarks from my Opera account unless the data on the servers has already been wiped.