Pywal on Mac OS not setting scheme and wall paper correctly

[weihong0827]

Im using Mac OS with Pywal and after installing python2 and all the necessary dependencies and install from the master zip file as instructed in the installation guide

The command is able to run normally, but it doesn't seems to generate the correct output and behaviour

I have tried to use different photos, but none of them changed the background image, and the colorscheme that the program produced is the same all the time.

[robwaz]

Please see #715