If I remove [this if-check (sessionHistoryInParent)](https://searchfox.org/mozilla-central/rev/0db73daa4b03ce7513a7dd5f31109143dc3b149e/browser/base/content/tabbrowser.js#1981), the test will succeed.
Bug 1656768 Comment 9 Edit History
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If I remove [this if-check (sessionHistoryInParent)](https://searchfox.org/mozilla-central/rev/0db73daa4b03ce7513a7dd5f31109143dc3b149e/browser/base/content/tabbrowser.js#1981), the test will succeed. And it seems that the pref for sessionHistoryInParent is enabled when I add `--enable-fission`.