Bulk upload of files (multiple GB) to "my files" using the browser is not reliable. Very often only the folder names are uploaded but no data inside. That requires manual checking of each folder to see if the content was uploaded too or not.

When as a workaround, syncing the data using the Proton Drive app is chosen, it gets reliably uploaded and is stored in "Computers". Now the problem is that the data can't be moved to "my files" where I want it to have it stored.