After switching to Lightning Experience, users may notice that Related Lists do not sort in the order defined in Page Layout settings, even though the sort order appears correct in Salesforce Classic.
Users can manually set their preferred sort order for Related Lists in Lightning Experience. This preference is saved per user and persists across sessions.
The steps above do not apply to the following Related Lists. These cannot be sorted in Lightning Experience:
Vote and Comment on the Idea Exchange to Enable global default sort for related lists in Lightning.
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