History graph shows this: 
mini graph card shows this: 
Console says this

and this

Did you see this issue before updating to 0.2.3 or only after?
@isabellaalstrom I think I managed to recreate this. Apparently, Number(null) equals 0, which made history entries with null as state pass straight through the isNaN check 馃槙
I see! The issue was present before 0.2.3 as well. Not that regularly occuring perhaps, and for me it's alright since this will be gone in an hour or so by now.
Okay, thanks for the issue, should be fixed in the next release!
@isabellaalstrom New version available v0.2.4, this should hopefully be resolved.
Can confirm!