GitHub website not working properly (in my PC)

Hello everybody,

I have some issues using github (website) in my PC.
For some reason, something goes wrong when I try changing between branches (clicking on branches droplist, where master is selected by default). Instead of list the branches, is showing up a happy cute smiling cat animated icon.

Something similar happens when I try to create a new pull request. I cannot change base/compare branches using the droplists. This time fails showing up the branches list (a very thin dialog appears without visible content)

This happens only in my PC. I tried this on my laptop and works fine, but in my PC (with windows) fails (tested on Firefox and Google Chrome). Some ideas?

Thank you for your time!

I see that cute cat myself if I’m having connectivity issues. Are you using the same connection with your laptop and desktop PC?