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I've recently switched from KDE to i3, and whenever I use nm-applet to connect to an existing wifi, it asks me for the password. I've launched kwalletmanager to properly unlock the kwalletd, but it still doesn't pick up the passwords from there. I've tried to readd the password via the connection settings of nm-applet, didn't help.
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What do you mean "anymore"? If you've been using plasma are you absolutely certain that you used nm-applet and not plasma-nm ? The latter is integrated with Plasma/KDE and supports kwallet, the former isn't. Configure https://wiki.archlinux.org/index.php/GNOME/Keyring for nm-applet.
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