I don't think this is covered by the Defect "Responses on the main body need to be richtext", but apologies it it is.
(I'm running at 1400x900 resolution, which I think is not unreasonable).
Thanks.
Thank you for your suggestion. We are adding this feature request to our tracking system to investigate it further.
Upcoming changes to the Forum template include displaying all responses to the thread on one page. This means that the topic map is no longer needed. These changes are coming in a future iteration.