Propper offline functionality/syncing with PWA

[corbin-auriti]

Currently the PWA renders offline, but when trying to type text or create a new note, it keeps deleting the text.
This may be able to be done with the Background sync feature in ServiceWorker

[Aragur]

@QingWei-Li is there any ETA for this feature?
That's a killer feature for me.
Do you need any assistance?

[clach04]

#101