Directly copying tracks between projects isn't supported right now. Here are some workarounds:
Just need a duplicate?
Click File and select Save as...
- Click track settings and select Export.
- Import the downloaded file into a different project.
Adding regions to the loop library
- Hover your mouse over a region and click Edit.
- Click + Add to loop library and Add loop.
- This loop can now be added in your other projects using the loop library. Your own loops are private, so they'll only appear in your own loop library.
- Click My Loops in the loop library to show your saved loops.