Ubuntu – taking screenshot with menu activated using keyboard

You can use this application called shutter

Alternatively run the following to install the package via a terminal (Default keyboard shortcut: CtrlAltT)

sudo apt-get update && sudo apt-get install shutter

It has options to capture dialog boxes, tooltips and pretty much everything that you will ever encounter or need to take a screenshot of.

To capture a drop-down menu with Shutter, open Shutter after installing it and click on the button pointed by the arrow in the screenshot below:

After clicking, you'll have a timeout before you which you can select a drop-down, keep the drop-down clicked until the timeout finishes to capture the selected drop-down menu

After capturing, click on Export button to either save the file to your desktop or host it on an image hosting service or FTP it or even push it to your Ubuntu One account.

You could also set a timeout and click the Window button and choose your browser from the dropdown. Before the timeout reaches 0, select the drop-down in the site to take a screenshot of the drop-down menu along with the website open.

I just stumbled upon the answer...

Apparently Gnome Terminal is different from "normal" apps and has accelerators turned off by default? (Why is this?)

Anyway, the solution was to go to Edit menu -> Preferences -> General and enable the "Enable mnemonics" checkbox.

Also curious, why are they called mnemonics in this case but accelerators" in the official help documentation? Perhaps a consistent naming should be adopted to make it less confusing? I'd vote for "mnemonics" now that I'm aware of that term (I'd never heard of it before today); "accelerators" has too many other meanings.