I know I reported this some time back still Opus 13 now 6.3 but I couldn't seem to find the post. I know you told me to recheck it after the some update that was coming out but I'm not exactly sure what causes this as I've not had the time to play around with it.
I had a folder called Cartoons on my LAN share that I moved from P:\Users\MyProfile\Documents (left side) to
P:\Users\MyProfile\My Pictures\Images (right side)
I couldn't find it in the Folder Tree or the File List which was set to thumbnails on the right side. In the latest DO you usually get that darkened highlighting of folders in the destination that are in process of copying/moving using server side caching (SSC) which then are shown in regular File List color after they are 100% complete. But I got none of that that I saw.
Cartoons wouldn't show in the Folder Tree at all. I tried F5 several times with no luck even tried using my refresh button. I had several files on the destination that I wanted to include in the Cartoon folder. I even added a new folder Sculptures to
P:\Users\MyProfile\My Pictures\Images
which showed immediately but still no sign of the Cartoons folder in the Fiolder Tree although it did show-up in the File List at some point.
I finally decided to close the lister and reopen it. That did the trick but I shouldn't have to do that.
I setup the same scenario that happened last night except I created a brand new folder in the same location as it was last nigh on the LAN with random image files to move to the destination/right side and a new folder on the same LAN drive also with random folders and files to move it to and it worked without a hitch except the focus was lost to the parent directory for some reason. I tried doing the move to the Folder Tree and then to the File List both worked perfectly.
When this problem happens it's very obvious but it's not consistent or maybe the fact that I had File Explorer open at the same time forced an update to the system that's not happening with DO alone or maybe it has something to do with the new folder tree in the file list coding? I closed File Explorer and tried it both ways yet again and it worked perfectly.
It's a Windows 10 computer, a different OS's at work than a NAS. Normally it would have been doing a lot of file downloading and saving to a different drive but that particular day the app wasn't working and I remember at one point the CPU was like 5%, single digits. I remembered because i've never seen it so low.