There’s no smiley “window” in the new forum - you just start typing in a smiley and a hint appears. There are actually plenty of codes that show different things though.
Rather than list them all here and re-invent the digital wheel - here’s a website that will let you see all the smiley’s and clever icons that you can use.
I’d post some confused smileys but I’m not sure how! - What do you mean by typing in a smiley? - Makes me realise that smileys are actually quite important. Saying something ‘tongue in cheek’ is very hard to convey without one.
You either copy from the link John posted or start a smiley beginning with a colon, so (for example) - to get that, I just typed a colon followed by an l (no spaces) and it brings up a list. If you use the link, you just click on the one you want and it copies it to your clipboard and then you just paste in here. You can see if it’s worked in the preview box on the right while you’re typing :