But, how exactly does being able to install a keylogger on someone's computer mean you can also break memory integrity and steal data from the browser's memory?
From what I know, windows keylogger "services" were very popular some 10 years ago and hence the banks rushing to "fix" it.
On Windows at least, any process can read any other process' memory as long as it's running under the same user.
(And also criminal to have a password max, short of like 1MB — even then the only reason for the limit is to slightly reduce the harm of some kind of weird DDOS against your login endpoint - whenever I see a password max I always assume this site is so dumbly implemented that they aren’t hashing my password but storing it in plaintext or reversible encrypting it.)
I mean, just think this two steps further. Hackers change input, and banks change input, so hackers == banks? But hackers also change what is displayed on the screen, and password fields change what is displayed on the screen, so hackers == password fields? Pressing my mouse button on the "reply" button changes what is displayed, so hackers == my mouse?
That's not the premise you stated earlier. That was: "Banks and hackers do the same thing by modifying the text during the copy and paste workflow", which completely ignores what kinds of modifications are happening.
> Copy and paste workflow is well defined and established concept by now. That bad actors are doing it doesn't mean you should.
See? You're doing it again. Banks are not doing what "bad actors are doing". Banks are doing something else.
> No point in exaggerating my premise and ridiculing me.
I am not exaggerating your premise and ridiculing you, I'm continuing your logic to show its' flawed premise. You stated that "banks and hackers are doing the same thing", and the reason it's the same is due to the literal operation being the same. Why can't I extend this logically to other operations that are the same? A password field changes what is displayed compared to my input, how is that different from a hacker changing what is displayed compared to my input?