[#1415] Notify adding and removing of handlers.

Problem description
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Describe the problem that these changes wants to solve.
This content should be created when a ticket is submitted and just link
the ticket or copy paste the ticket description... or find a way for
linking this review to a ticket.


Why we got into this (5 whys)
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Mainly used for bugs.
Describe why we got this problem in the first place. What went wrong.
Repeatedly ask the question “Why” (up to 5 times) to determine to
cause of this problem.


Changes description
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Describe how the problem was fixed.
What changes were done.
What actions were performed.
What was not done yet and link to the ticket for the still to do work.


How to try and test the changes
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reviewers @some-dude @another-dude

What code / repositories were affected. Where is the code.
If the code in only on a single feature branch, no need to say something
about the code.

How the changes can be tested and verified as an end user.
A list of steps to follow for checking that everything is OK.