I do not understand how some password management browser extensions use some online storage system like DropBox or Google Drive for 'synchronization' among different computers and browsers. All I know how to accept with little confusion is that user makes an account with the password management extension company, user signs in to websites of interest on which he has his web accounts (like for forums, webmail, other kinds), and if first time while using the browser password extension, the extension program can save the "login" combination, ON THE EXTENSION PROGRAM's ONLINE SITE. Now when the user goes to any of his computers which may also have the needed browser extension, user can sign in to whatever site for which he earlier saved his login combination.
Now I have been reading through several online web searches about different password management programs. Some of them do not keep the users login combinations on the company's online site; but instead, the user accomplishes the synchronization among browsers and devices through some online file storage system like DropBox or Google Drive.
I do not understand. Someone explain what the user would do to use something that way. I only have experience with Norton Identify Safe (cloud for one person, and LOCAL for me/mine), and LastPass (which only keeps stuff on 'cloud' that LastPass runs).