I upgrade from Kubuntu 16.04 to 18.04 and after was Google Chrome really slow at starting. It took about half a minute to start and this annoyed me a bit.
As I always do when an app is in trouble I start it from Konsole and got this error:
Failed to call method: org.freedesktop.Notifications.GetCapabilities: object_path= /org/freedesktop/Notifications: org.freedesktop.DBus.Error.NoReply: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.
I search the net but could only find information about the notifications-demon and I tried to install it with the recommendation from others (https://askubuntu.com/questions/52960/notify-send-does-nothing-yet-libnotify-is-installed#53644) but still Google Chrome was slow.
At a site I read something about the notification widget was not added to the desktop panel or desktop (sorry – lost the reference) and right after I added the notification widget to the panel Google Chrome start right away.