The PR contributor was not paid either to investigate the bug, reproduce it, write a patch and test it. However instead of raising a "don't work, please fix" b

The PR contributor was not paid either to investigate the bug, reproduce it, write a patch and test it. However instead of raising a "don't work, please fix" bug s/he took the time to do all that. Anyone that went to such length deserve basic courtesy, whether the code is accepted or refused. Refusing a patch because it is "boring" is not respecting the time people dedicated to your project. I would understand refusing because the patch makes an unwanted compromise on performance and the maintainer considers performance regressions as bug.