Pro Tour Punditry
Guru
Not on my screen, I don't even have anything that looks like "film strips"Well ok then......
Put whatever reply you want in the reply box. The bit you don't want revealed, just highlight it with your mouse or whatever you use, then go to that wee box of icons above the reply box. There's one there, between the camera and the film strips, that looks like a sheet of paper. Click on that, it will give a few options like strike through, something else, and spoiler. Just select spoiler, and the highlighted text won't show in the reply and the spoiler button will appear instead.