It was indeed possible in 0.17! Try it yourself: ctrl-f for the item, toggle with '!', item letter, toggle with '!', item letter, done!
And 0.18 killed this. (Why?)
Well, hey, on the bright side now when you ctrl-f for "shop" you get just list of shops, not list of shops
and all the junk they have.
And while we are on the shop topic, here is the tiny thing that also bugs Me:
When one marks a set of items for purchase, items that couldn't be bought along with the set, turn yellow. Very nice feature! Now the thing in 0.18:
If item 'a' costs X gold, you have Y gold and 2*X<=Y then item 'a' stays green after it was marked for purchase, but if 2*X>Y it turns yellow - as if game wants to tell you that you won't be able to purchase a hypothetical twin of item 'a' after you buy said item. In 0.17 it stayed green in both cases.
P.S. I haven't checked but
the last commit on the shop topic could have had this fixed (yellow-green thing not the OP issue).
Offtopic grunting:
0.18 was my least favourite release, and not because of the amulet reform - I think it was for the good. 0.18 brought a bunch of little annoying bugs that broke things which worked just fine in 0.17: aforementioned shop issues, apportation issue (target cycle included items behind walls, fixed in 0.18.1), finding stairs in shift-X issue (sometimes unreachable stairs were offered as closest, fixed in 0.19), fog issue (not fixed). Probably there is a couple more that I don't remember right now.
If you spot a grammar mistake in my post I will appreciate if you PM it.