I don't see a beta 8 tag https://hg.mozilla.org/releases/mozilla-beta/tags Can you please confirm the build id used in testing? I could not confirm the bug in beta 7.
Bug 1524028 Comment 17 Edit History
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I don't see a beta 8 tag at this time. https://hg.mozilla.org/releases/mozilla-beta/tags Can you please confirm the build id used in testing? I could not confirm the bug in beta 7 on windows.