I added a tag to a book (on the left), clicked on tag and got the erroneous results on the right:
They are erroneous because they lack quote marks in the selection argument. It would be better to have extraneous quotes than omitted quotes.
What is even more curious is the randomness of the results with the erroneous selection - it appears to pick up a random 2 of the possible 10 candidates for the error.
