Artborads erased and layers grouped when opening a file, Illustrator 2020
Illustrator 2020 (24.0.1), Mac OS Mojave 10.14.6
Whenever I close a file with multiple artboards and multiple layers, and re-open it, all artboards but one are erased (and renamed to "Artboad1"), and all my layers are grouped into one single layer.
Even when I fix the file, and save it, the next time I open it, the same thing happens.
All the contents in my artboards get grouped when I save my work with multiple artboards to an ai file.
If I save as an editable PDF all the artboards open just fine.
I think this is a very serious bug and should be solved as soon as possible.