This bug was filed from the Socorro interface and is report bp-cedd29f0-ed73-4cec-9509-221f80170601. ============================================================= There are 43 crashes in nightly 55 starting with buildid 20170505030252 (see ) so after the patch for bug 1359129 has landed. :handyman, could you investigate ?  https://crash-stats.mozilla.com/search/?release_channel=nightly&signature=%3DIPCError-browser%20%7C%20PDocAccessibleParent%3A%3AAddChildDoc%20binding%20to%20nonexistant%20proxy%21&build_id=%3E20170503000000&product=Firefox&version=55.0a1&date=%3E%3D2017-05-03T00%3A00%3A00.000Z&date=%3C2017-06-02T00%3A00%3A00.000Z&_sort=-date&_facets=url&_facets=user_comments&_facets=install_time&_facets=version&_facets=address&_facets=moz_crash_reason&_facets=reason&_facets=build_id&_facets=platform_pretty_version&_columns=date&_columns=signature&_columns=product&_columns=version&_columns=build_id&_columns=platform#crash-reports
I checked this out recently but there isn't any helpful information in the crash-stats. The frequency is much lower than before but I'll keep an eye on it. Right now... no idea.
Work is happening in bug 1376754