Was reading backscroll and it looks like no one answered Chris' documentation question in comment 29. If this is going to cause issues in webextensions (e.g bug 1596889) it should be clearly documented / explained.
Bug 1405971 Comment 36 Edit History
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Was reading backscroll and it looks like no one answered Chris' documentation question in comment 29. If this is going to cause issues in webextensions (e.g bug 1596889) it should be clearly documented / explained. Apologies if you followed up out of band.