For a while I was using Scatter and kept trying to paste my public key and then my private key into the key fields, but Scatter kept closing whenever it lost the focus. Then I remembered that one can generate a public key from a private key and several addresses in an HD bitcoin wallet and realized I only needed to paste the private key and Scatter then shows the public key associated with that address.

But new people might get frustrated if they don't understand this. There should at least be some prompt to tell you to paste the private key first so you avoid a lot of headaches.

I've been doing this only with my test keys because I think my internet connected machine could be hacked. I wish there was a way of pasting masked keys into another device (such as Trezor). For this reason I feel compelled to sit out the vote process until I know for sure.