Not OP, but there's not much to do about them - best way is to enter manually in the app at the time of purchase or write them down in a notebook and enter them in batch once in a couple days or per week.
If your cash spending is sufficiently small that you don't care much to tracking each cash transaction individually, you can just track money as a category instead of an account - just record an outflow transaction in your bank account when you withdraw.
If your cash spending is sufficiently small that you don't care much to tracking each cash transaction individually, you can just track money as a category instead of an account - just record an outflow transaction in your bank account when you withdraw.