as far as other plugins go, they were Kopf (but there is already Cerebro, which works fine), Elastalert (but I can se guys are already porting in to ES 5.X), Sentinl and auth bug with Kibana 5.1.1 and Searchguard (which is also resolved with kibana app, although currently in alpha version).
Oo, an of corse, some of our own apps, which needed upgraded python library and some minor changes to the code (this was my fault, forgot to test it)
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