Several of the comboboxes that I use regularly (the box to select syntax highlighting in the gedit statusbar, boxes for choosing smart playlist criteria in Banshee, etc) require me to click on them with the mouse, scroll down for awhile, then click on the item that I want. Being able to type into these boxes and have the list jump to the first matching entry would be a nice time saver.
So I'm wondering, has this been implemented in Gtk+ 3? If not, is there a bug report somewhere that I could subscribe to? And is there a technical reason that this hasn't been implemented, or is it a design decision. Since this behavior is common in all major web browsers, I'm sure I'm not the first person to think of this, but a few minutes of Googling didn't lead me to anything relevant.