GIMP 2.10 isn't included in Ubuntu 18.04 and is therefore unsupported. However, by the output from the bug report, you're using 18.10 (for testing purposes, I'm guessing)? If so, I recommend editing your bug description.
GIMP 2.10 isn't included in Ubuntu 18.04 and is therefore unsupported. However, by the output from the bug report, you're using 18.10 (for testing purposes, I'm guessing)? If so, I recommend editing your bug description.