In that case, there's not a bug here. To fix it you'd either have to modify the font size or get a larger screen.
Looking for Theme ?
Is there a list of currently supported themes somewhere? When I am searching I am only finding stuff that has not been updated in many years.
Even with the 4 themes that come with NodeBB, it seems like only Persona is updated regularly.
I wanted to use Lavender but it has not been updated in long time and the link for the guide does not work.