Isn't that Handler also used from the plasmoid and KCM, which is in a separate process from kded?

In D28698#644695, @broulik wrote:

Isn't that Handler also used from the plasmoid and KCM, which is in a separate process from kded?

It is.

Yes, but I don't see this being a problem

In D28698#644698, @nicolasfella wrote:

Yes, but I don't see this being a problem

I think this was done this way to make the kded module used only when either the applet or KCM is running. It was Lukáš Tinkl who implemented at the beginning of Plasma 5 so I don't really remember the details. Part of this was also done for https://bugs.kde.org/show_bug.cgi?id=338513.

Actually it was me who pushed this, Lukáš just did some changes to it.

Here are some details: https://cgit.kde.org/plasma-nm.git/commit/?id=81839a1566d0c0209a308d71b03837f996a19c96

I see, that makes sense

I see that we already initialize the secret agent right when the kded module is loaded, but I see a potential problem in showing a notification using a fallback backend (the ugly notification which pops on the top of screen) when Plasma notifications are not ready yet.

In D28698#644703, @nicolasfella wrote:

I see, that makes sense

Actually we already initialize the secret agent right when the kded module is loaded, but I see a potential problem in showing a notification using a fallback backend (the ugly notification which pops on the top of screen) when Plasma notifications are not ready yet, because NetworkManager might be trying to activate a connection before Plasma starts.

(the ugly notification which pops on the top of screen) when Plasma notifications are not ready yet

Plasma ships a trick for that which means that we always get plasma notifications when plasma is installed regardless of if it's running.