for some reason i just assumed bubble would always yeld to pwa, or at least some similar feature for offline access, as default.
it doesn’t, of course.
nobody really does it now, in the no code universe, do they?
and i tried all the options offered above. none worked very well.
to me, this is what i was expecting:
open website.
go offline.
reload.
all visited pages will work.
ideally, some pages not visited will also work.
just like gatsbyjs.org
now, the weirdest part is…
go online.
install.
go offline.
everything should work!
i think gatsby doesn’t install… but it should, shouldn’t it?
the Pokémon demo almost works, but there’s just so many broken things, including bugs and not really working while offline, that i don’t honestly think it’s worth the trouble.
so, in the pwa aspect, i found it hard to come up with a quick instance of how it should work!
anyway, hope someone can help before i find the answers myself… 
cheers!