I have verified that this issue is no longer reproducible using the latest Firefox Release 116.0.2 (Build ID: 20230805021307) installed on Windows 10. I can confirm that the "Embedded Import" screen from the "Treatment A" branch of the experiment has the correct UI. Based on the above testing I am closing the issue as Resolved.
Bug 1848128 Comment 2 Edit History
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I have verified that this issue is no longer reproducible using the latest Firefox Release 116.0.2 (Build ID: 20230805021307) installed on Windows 10. I can confirm that the "Embedded Import" screen from the "Treatment A" branch of the experiment has the correct UI. Based on the above testing I am closing the issue as Resolved - Fixed.