Just seeing now, that this is actually a duplicate of Bug 610896 and that there is a (already better patch) attached there. Depending whether it is still mergable, we could reuse that patch or I will update the test cases in my patch later.
Bug 1741375 Comment 8 Edit History
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Just seeing now, that this is actually a duplicate of Bug 610896 and that there is an (already better patch) attached there. Depending whether it is still mergable, we could reuse that patch or I will update the test cases in my patch later.