I've been seeing this for a few weeks: the progress bar for the current item is working normally, but the "all items" bar never shows anything. Here's an example from a copy from an internal drive to an external:
I suspect that this isn't an Opus thing, as I don't think it appeared at the same time as an update. I'm running 12.24 x64 on Win 10 20H2.
Why would it matter if I was copying a single folder? Would it skip the count if the folder size had already been calculated in the source lister? I have "Folders / Folder Behaviour / Calculate folder sizes automatically for local drives only" set, but in this case both the source and destination were local drives.
The test copy I posted before was 3000+ files and 66GB. I've just tried copying another folder between the same two drives and it was quite happy to count the files and provide an estimate almost immediately, so perhaps I did something different last time? I also assume I'm suffering from selective amnesia - it's probably working perfectly well most of the time, but I'm only remembering the times it hasn't.
Looking at the files being copied, and the first screenshot above, almost all of the data was in a single file of 66.1GB. Does Opus have to see a minimum number of files being copied across before it starts counting? Perhaps this massive file was the first file to be copied, and by taking ten minutes to copy, it delayed everything else?