Presumably this is a long standing issue. If the OOP iframe case is fixed by bug 1684795, this is for non OOP iframe case. Setting S3 since (I suppose) it's a long standing issue.
Bug 1691346 Comment 0 Edit History
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Presumably this is a long standing issue. If the iframe is an OOP iframe, it's fixed by bug 1684795, this is for non OOP iframe case. Setting S3 since (I suppose) it's a long standing issue.