UX: Fix mobile PM nav for regular users (PR #14007)

Follow-up to 016efea

Before: Screen Shot 2021-08-11 at 10 56 21 AM

After: Screen Shot 2021-08-11 at 10 54 38 AM

(admin layout, for reference) Screen Shot 2021-08-11 at 10 57 30 AM

GitHub

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