Ctrl+Alt+E Yields € symbol in addition to switching to edit mode.

If I'm in "both" mode, and press Ctrl+Alt+E to switch to "edit" mode, It will work, but it will also put an `€` in the current cursor position.

An `event.preventDefault()` should probably fix this, however, this should only be done, if there's actually a switch happening (meaning: If I'm *already* in edit-mode, please don't `preventDefault`, or we won't be able to type € symbols any more).

**To reproduce**

* (you may need an european keyboard layout, I'm not sure)
* Set any pad to "both" mode where you can see the editor and rendered html at once.
* Make sure, your focus is in the editor, so you can actually type
* press Ctrl+Alt+E

**Current Result**
* The view is being switched *and* you also get € at the current cursor position

**Desired Result**
* when *already* in edit mode: just type the €
* when *not* in edit mode: just switch to edit

I'm not sure if other (Ctrl+Alt+V or Ctrl+Alt+B) shortcuts interfere with anything, they do not on my layout. But this could be a general pattern, I believe.

Reproduce the shortcut while focused in the editor, first in both mode and then in edit mode. Find the keyboard shortcut handling for switching modes and verify that the € character is suppressed only when a mode switch occurs; done means switching produces no € while typing € in edit mode still works.

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