• Describe the issue
  Pretty much every FTBFS bugs has "file build.log too big, will only attach last 1024 bytes" and "file root.log too big, will only attach last 1024 bytes". 1024 lines would be somewhat useful, but 1024 characters is just the spew that mock outputs at the end of every build and contains no hint why the build failed whatsoever.

In addition, the message does not specify what kind of failure was encountered. koji knows this and says to look either in root.log (dependency issues) or build.log (build issues). It would be great if this could be included in the bug message.

• When do you need this? (YYYY/MM/DD)
  For the next rebuild.

• When is this no longer needed or useful? (YYYY/MM/DD)
  When packages stop failing to build.

• If we cannot complete your request, what is the impact?
  Maintainers have harder time solving FTBFS bugs.