bubersson/humla — comment on commit b585b276e780bd868683186dbe86e7bebf89af57
File:  line 0
By bubersson:

Online/offline fires only when the connection state changes - so if the page is loaded only locally (html5 cache with manifest, TODO) you can't say if the browser is online or offline based only on humla.online.

But those are really only corner cases.