Thanks Marco. Would it be possible for you to uses mozregression to help track it down? See https://mozilla.github.io/mozregression/quickstart.html I can also give you a list of builds to download and test if that's easier.
Bug 1543657 Comment 6 Edit History
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Thanks Marco. Would it be possible for you to use mozregression to help track it down? See https://mozilla.github.io/mozregression/quickstart.html I can also give you a list of builds to download and test if that's easier.