When copying an entire line, the game inserts a space at the end (or might be that it inserts a linefeed but it gets converted to space when pasting). Why is this a problem? If you shift-click an item and copypaste the entire name into the GMS window, you won't get any results because of the space that's not part of the item name (GMS could also be a word search instead of a substring search, but that's a separate issue).
I've hit this problem many times, and I should be aware of it... Yet today I once again spent several minutes wondering why I can't get any results for an item, not even the one in my own shop. I checked and double-checked the QL and price ranges, tried every category (some items being in weird categories is yet another problem), to no avail. Until I remembered that damn space.
Fix please.