“LocalStorage is lazy” and “server storage is more fun” are not good reasons to avoid localStorage. Durability and reliability are reasons enough! - LocalStor

“LocalStorage is lazy” and “server storage is more fun” are not good reasons to avoid localStorage. Durability and reliability are reasons enough! - LocalStorage will silently drop concurrent writes sometimes. One of my first major projects at Notion was moving our client-side change queue from LocalStorage to IndexedDB because we found that localStorage would just… lose data. One of our engineers wrote a simple HTML page that wrote sequential data in a loop, and another thread read the data to verify it. We saw loss of 5% or more in some conditions. - LocalStorage is treated as almost-ephemeral by the browser/OS. We found that under disk pressure, many engines will happily clear some or all of your LocalStorage keys. Browsers seem more reluctant to drop IndexedDB data. - If you want any kind of “scan” over a bunch of data, or if you want to store larger/binary data, IndexedDB can get you better performance. - Third party scripts like analytics, customer support chat, etc happily spray data into LocalStorage, and you end up competing with them for scarce quota. IndexedDB has better namespacing and budgeting - plus, if you use entirely IndexedDB, you can nuke LocalStorage to reclaim quota from those third parties.