tabs getting turned into spaces within code tags?

In this post I could swear that I pasted in code with tab stops, but the indentations were turned into spaces. I remember that this used to be standard, but somehow something was done to the forum so that tabs could be preserved when copied into the forum. Anyone remember how this was done?

I’m using Firefox on the Mac, in case that makes a difference.

(The old “quote the post and copy the code from that” trick, which how we used to get the indentations in the old days, is working for that post.)