Strange focus border since ExDoc 0.36

[garazdawi]

If you go to https://hexdocs.pm/elixir/Kernel.html using Chrome, Edge or Safari (not firefox) and then click on another module (for example Atom) and then do a pagedown, there is a purple border created around the main context that should not be there. It seem to be related to focus somehow as I cannot take a screenshot of it as it then dissapears... the same borde also appears in at erlang.org/doc.

I clicked around in the different version of Elixir and it seems like the fault was introduced in ExDoc 0.36 which I assume is the swup release.