QA:QA Backwards Compat

Build 1427 on new-storybook-theme-switches
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Baseline History
Build 1427e79dff1
Current build. There are unaccepted changes, so build 1398 is still the baseline.
Build 13982d6dd4e current baseline
Accepted by Josh Wooding.
Build 1370768ef09
Accepted by Joana Moreira.
Build 13635d8e5c7
Auto-accepted
Build 13463952857
Auto-accepted
Commenting is disabled because there's a newer build on this branch