Developer had to revert to older Xcode to make it work, plus some fancy reconfigurations, and he posted an article with technical details that might help other developers running into same issues maintaining compatibility with older macOSes. Problem was due to Apple making it more difficult with each release of macOS to maintain compatibility with older versions of OSX/macOS when using newer xcode and other developer tools. PS, 5-stars for the excellent work by developers once this was reported, to fix the problem in a little over 24 hours. If you don't or can't get the newer build with the '-1' suffix from MacUpdate, go direct here and download: Also, note that 'About GIMP' from menu will report same 2.10.8 version number for either build, so don't go by that. Not sure when or if MacUpdate will recognize or pull the newer build, as both are still 2.10.8. The original build that crashed is named 'gimp-2.10.8-x86_64.dmg' without the '-1' suffix. Initial release of GIMP 2.10.8 on Nov 9 crashed on earlier versions of macOS (10.9, 10.10, 10.11) at startup.
