Looks like something recently broke pull to refresh. I can reproduce the issue on Nightly with or without Navigation Bar. However, in Beta, I can't reproduce the issue even though the same code is there (Navigation bar is not enabled but the same code is running) Something recently broken this in Nightly.
Bug 1911198 Comment 3 Edit History
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Looks like something recently broke pull to refresh. I can reproduce the issue on Nightly with or without Navigation Bar. However, in Beta, I can't reproduce the issue even though the same code is there (Navigation bar is not enabled but the same code is running) Something recently broken this in Nightly. I'll find the regressor.