I have Ubuntu 15.04 with all the latest updates on 64bit machine. I prefer to use Mate since it so far was the only desktop manager that did everything I wanted and did none of the things I do not like.
For some reason the indicator area in my panel only shows the volume indicator. There is no icon for the network-manager applet (but nm-applet is started!) there is not icon for the battery status, all other icons that were previously there are now gone.
There also seems to be no way to add an indicator applet for which of several configured keyboards should be used (previously there was an applet where I could select between en/es/de etc)
How could that happen and how can it be fixed?
The internet is unfortunately full with instructions which either do not apply (older versions etc) or make things worse.