This may or may not be a bug thats why I am posting it here.
I used the devtools plugin to create an inheritence theme of Antimatter ( following the tutorials on the learn site ) everything works as expected but when I check the themename.yaml the Antimatter theme is listed 1st so inheritence doesn’t work.
I repeated this with a few other themes and got the same result.
The ‘base’ theme is always listed 1st if you create the theme with the devtools(1.0.8) plugin
UPDATE: It is/was but now fixed https://github.com/getgrav/grav-plugin-devtools/commit/40a5a86d89df08ee1925af40d5a5c49481c6ad1a