I downloaded the Monero GUI 0.17.1.9 .dmg, but when I opened the disk image, the GUI app icon has a slashed circle across it, it's 'Not Supported on this type of Mac'. I previously ran v0.13.0.4 or the version just prior to it.
I'm running macOS 10.13.6.
How do I get this to run on this machine? Or is there an earlier version I have to use?