Now I guess it's time; I'm a new user of the SharkJack and I have exactly the same problem. And that in May 2021! Are you serios @Hak5? 😅
Sad.
EDIT:
Really? The Packages-list only contains a Fake-Package?
Package: fakepackage
Version: 1.0
Depends: libc
Section: libs
Architecture: mips_24kc
Installed-Size: 1
Filename: fakepackage.ipk
Size: 1
SHA256sum: 136b28f8a6a0c99f579e9b1d0dab069000ee404bdcc832574a83180ba6973e92
Description: Fake Package.
For anyone who has problems with this in the future:
Just uncomment the second line in the file "/etc/opkg/customfeeds.conf" and you are good to go.
