Adding the Package available at https://github.com/facebook/sapling/archive/refs/tags/0.2.20240718-145624+f4e9df48.tar.gz to DejaCode is generally successful, but there is a problem with the Inferred URL:

Package URL: pkg:github/facebook/[email protected]%20f4e9df48
Filename: sapling-0.2.20240718-145624-f4e9df48.tar.gz
Download URL: https://github.com/facebook/sapling/archive/refs/tags/0.2.20240718-145624+f4e9df48.tar.gz
Inferred URL: https://github.com/facebook/sapling/tree/0.2.20240718-145624 f4e9df48

Note that the Inferred URL has a gap (space) where there ought to be a + (plus) sign.
If you click on it in the DejaCode user UI you get a 404.
If you copy the whole thing, and edit it to restore the + then you get the intended repo page.