>However, now that you changed the formatting of the header, the header may turn out to be just too wide itself (compare message 1630754 with this one) because the textboxes for various environment settings (OS, database etc) add up to more than 940, which then forces the whole message frame to that larger width, so I have to scroll left-right again.

The headers have this format for a very long time.

>I may solve it myself meanwhile... this monitor is on its last legs, and I may buy a new one with 1200 instead of 1080px :).

But, yes, the recommended settings are 1280xsomething.