cannot log in on keybase app on apple

Hi, i use keybase on my pixel phone. I can log in in the browser and on the pixel phone app. But I cannot log in the computer keybase app on a Mac Book Pro 2008 with Yosemite 10.10.50.
Then " opps somtething went wrong appears", see the picture. I need to add one more device (the apple mac book), but I cannot add it on the pixel phone and since I cannot log in on the computer keybase app, i cannot add it anywhere, because i can also not add an device in the browser. please help me, how can log in on the computer app/ add another device? Also i do not know how to access the commmand lind in the browser, if I need to do that. Please help me. with regards!

Start by reproducing the login failure in the Keybase Mac app on macOS Yosemite 10.10.50, then compare it with the successful browser and Pixel app sign-ins. Done means identifying why this device cannot be added or documenting a verified way for the user to sign in and add the Mac.

Written by the indexing model from the issue text.