First off, thanks for this! I was just wondering what would become of this app when my laptop gets upgraded to 10.15, and you're already here (before a few paid apps I'm waiting on even).

Second, should this be able to run on 10.12? I know I can use the old version, but was just curious if the compatibility was a "new at cocoa" issue or if the ruler is using some fancy features that aren't in 10.12.