Hm, sometimes I feel that the review process involving me gets too far from the original issue that was too be solved by a PR :) But possibly that is not only due to me... Though one could also say that this is just collaboratively improving related code, which is good to happen as well... ;)

Having said that...
I cannot see anyone using EventManager.blur now anymore, so unless you are in your code, please remove exposal in the API. Possibly can also be inlined now, as there are only two internal usages, and one is inside a `hasFocus()` branch already.