I don't think Tekkub has been playing the game in about two years or so. The last update to Gnomish Vendor Shrinker was for patch 7.0.3 and since then the game's API has changed (looking at you, SoundKits) and with Battle for Azeroth, the poor addon is gasping for breath.
It isn't totally dead, just mostly dead. The SoundKit bugs are easy to fix, but when you open a vendor window in BfA then scroll up and down the list, the item list bugs out.
Is another author allowed to fix and update this lost wonder of an addon? What about the rest of Tekkub's addons that may need a look-see?