I used @dcb’s excellent DayOne to Obsidian script to import about 3,000 journal entries into Obsidian, and the only downside is that multiple entries from the same day are imported as separate notes with lettered suffixes, e.g. three entries from today would appear as 2021-05-25, 2021-05-25a, and 2021-05-25b. When I search for entries “on this day” in history, I can’t get the search to find those suffixed entries, I only get the first entry of each date in the past.
Being able to merge notes would provide an obvious solution to this problem because I could just find all of the entries with lettered suffixes and merge them into one note that appears in my search query for "On this day" for Daily Notes.