Moving over the screen the cursor sometimes changes from theme
Every desktop has its own way to select the cursor theme
Because we want to have a consistent cursor theme we have defined on all our desktops that we use breeze snow.
Navigate to this folder /usr/share/icons/default
You will find the file index.theme with this content (fix for mouse in plasma changing all the time).
Change here also to the correct cursor theme
[Icon Theme]
Inherits=Breeze_Snow
If you want an other cursor EVERYWHERE, you need to change this one too.
THE CURSOR theme IS NOT APPLIED?
DID YOU TRY
TURNING IT OFF
AND ON AGAIN