Mega.nz: Silent data corruption (folder removal)?

I've experienced a very strange issue recently: my MEGAsync linux client crashed yesterday. I've launched it again and it asked me to log in so I did. Today I've noticed that one of the synced folders (I'm using selective sync) has completely disappeared from MEGA without any traces, it also disappeared from the client's sync list. Fortunately, I had a local copy which is still intact. An empty folder named "MEGASync" appeared in the root folder of MEGA.

So, it looks like MEGA might silently destroy your data under some unclear circumstances. Did anyone experience anything similar to that? Is there anything I can do to restore my data if that happens?