I am using Debian testing branch.
Installed Google Chrome from Google, not Chromium from Debian repos.
Problem is that every time I launch the browser I get an additional popup from kwallet.
This is annoying because superfluous, it makes no difference if I cancel out or enter password, Chrome will log me in both ways.
How can I remove this behaviour without uninstalling kwallet altogether?

The reason is that kwallet has detected a relevant piece of code in the page; one way yo stop it is to open kwallet for another application and leave that application oipen. (I open kmail and leave it open.) Then kwallet will remain active but not pop-up unless you make an entry in whhat it thinks is a relevant part of the page.
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As an alternative to leaving another application open, you can adjust KWallet to close after a certain amount of time, or when the screensaver enables itself for instance.