Some educational institutions host legacy versions like iMovie 10.2.5 on platforms like ICS 1-to-1 Google Drive for students with older hardware.
: If you have previously "purchased" or downloaded iMovie (it is free with most Macs), open the Mac App Store , click on your Profile/Name in the bottom-left, and find iMovie in your Purchases list. imovie 10.2.5 dmg download
Downloading iMovie 10.2.5 DMG offers several advantages: open the Mac App Store