Why do you need to prevent users from saving in a banking app? That seems like attempting security by obscurity. Which doesn't work. The data is on the user's machine which means the user has the code.
And then your next requirement will be to disable the "View Page Source" option, and then to disable the browser's web development tools. All of which allow the user to see (and copy) the page's HTML. This is a futile path to go down.
posted 1 year ago
And, I'd like to stress again that it'd achieve no security improvement. There should be nothing in the page that imperils security if seen by the user. If this kind of thing is considered as enhancing security, then something has been designed profoundly wrong (or security concepts have been misunderstood).
It's pretty simple really: The user doesn't get anything to say about how your server works (imagine if they could!), and you don't get anything to say about how the user's browser works. If the user isn't allowed to do something with some data, then you shouldn't send that data to the user.