Describe the bug
When looking up a fish, any "special" locations where the fish can be caught are shown as empty strings. By "special" locations, I mean the locations of the legendary fish or any floors in the mines.

To Reproduce
(On Stardew 1.6.9 beta)

1. Lookup a legendary fish or a fish that is caught in the mines.
2. See an empty string in "locations" under "Spawn Rules".

Log file
https://smapi.io/log/9b203f9fdeac4de3835a7f093dd4f505

Screenshots