Collapse Terminator Icons on Dash to Dock

It's unlikely that I am the only one experiencing this issue, so please feel free to mark this as a duplicate, but after an hour of googling this I am unable to find the issue; likely due to me not knowing the terminology to use.

Anyway, less of the verbose: when I use the shortcut ctrl+alt+t to open Terminator, in the dash to dock, it doesn't collapse the items into one, leaving my dock quite cluttered. One thing I have noticed is that this doesn't happen when I open terminator using the dock icon, and that the shortcut seems to be opening "x-terminal-emulator".

Is there a way to solve this?

In the below screenshot, the top icon is two instances of terminator open, the further 2 are what opens with the shortcut, instances of x-terminal-emulator.

Screenshot of dash to dock with terminator open:

After more researching, I have found an answer (whether it is "the" answer is another question).

My problem was that to change to Terminator I was using the command:

sudo update-alternatives --set x-terminal-emulator

Then setting it to emulate Terminator rather than run it.

To do this on GNOME Ubuntu > 12, instead use:

gsettings set org.gnome.desktop.default-applications.terminal exec terminator