BeamCopy
Drive to Drive copy, done on Google's side
Setup needed: paste your OAuth Client ID into CLIENT_ID in index.html.
Free trial: one copy, up to 1 GB.
Your Google session expired. The copy is paused.
Choose what to copy
Exports the files shown by the filter.
Find a file in my Drive
Find duplicates
Checks the "Copy into" folder and all its sub-folders for files with the same name and size in the same folder. The oldest one is kept.
History