Does the browser synchronize any site data between clients?

Question

JavaScript

I'm working on a video player. There is no access to the server. Now all user settings are saved on the client. Question: if I have synchronization enabled in my browser, is there some kind of storage (indexedDB, localStorage, cookie, cache, whatever) that the browser will synchronize between devices?

Answer 1

In general, none of these will be out of sync. Cookies can, in principle, be synchronized, but you certainly should not rely on this when developing an application.
If it is not possible to change the logic of the server, but it is necessary, maybe introduce a proxy between it and the client, which will, in particular, implement additional logic on its side?