default note color

How would I select auto-varying note color?

It has been posted in features requests :
https://zhornsoftware.forumotion.com/t854-random-background-color-option-for-new-notes

Maybe it will return in the next version ?

It's still there, but it's pretty much a hidden extra now - there's no UI for it.

In Settings, on the Appearance tab, set the colour for new notes to be either 253,253,253 or 254,254,254.  You'll see the colour preview change to show that it's been recognised as a "random from selection" or "completely random" setting.

Tom