Not a major issue (as a non-sub), but where can I see what book puzzles I have solved?
I got a few freebies (10 year anniversary one; and I think one for the site reaching the 19 or 20 million solved puzzles mark), which came in PDF format. Occasionally, I do have time to waste ( :D ), and solve a puzzle from those.
Obviously there won't be that many book puzzles for me to solve, but I can imagine that it could be rather useful for those who have gotten many books (especially in pdf format), that they can see whether or not they have solved a particular puzzle and submitted a solution, before they spend time doing the (same) puzzle again.