The output from running a buildfarm step is the output from running a command such as make check followed by any relevant log files that the step creates. These log files can get quite large, and in some cases there are quite a lot of them. Up to now the buildfarm server has just show all of this in an undifferentiated text blob. That has made finding out what might have gone wrong not impossible but not as easy as it could be, and there have been complaints about it over the years.
A few days ago I implemented a new way of presenting this information. You still see the command output, but instead of showing the log file contents you see a list of the log files. Click on one log file and it will show you the contents of that file. Click on it again and they are hidden again. So if, say, a TAP test fails at script number 12, you can quickly locate the regress_log_012_mytest.log and associated server logs, without having to scroll through thousand of lines that don't interest you.
You can still see the old format if you need to - the page for each stage has a link to the raw log.
I hope this will enhance the usability and usefulness of the buildfarm.
Thanks to Kori Lane for pointing me at the JavaScript gadget that is used to implement this.
Update: All issues now resolved.