"Save" in miniPaint forces Save & Publish

Hello everyone,

I’m having struggles with the Asset / Image Editor (miniPaint).
When I’m editing an image and press “Save” (not the Save & Publish!), the latest version is directly published and I’m not able to schedule this. Only after this publish, I’m able to republish an old version and then schedule my new one - but this is not a workflow that i can put to my customer …

Any ideas what i’m doing wrong or if this is an already known issue?