Switching User-Agent in Opera

Question

How can the user agent be changed in Opera?

The per-site preferences (tab Network, field Browser identification) lists

• Identify as Opera
• Identify as Firefox
• Identify as Internet Explorer
• Masquerade as Firefox
• Masquerade as Internet Explorer

But can it be set to an arbitrary string (for example, googleinstantisreallyirritating)?

Opera version: 11.11

Answer 1

Opera support document indicates this is not possible. The possible choices are the numeric identifiers, which correspond to each user agent mentioned in the question.

This comment (admittedly, over a year old) by an Opera employee also confirms the same.