claus - 11:40 pm on Mar 13, 2010 (gmt 0)
Opera STILL has no way to make a custom User Agent string!
This is extremely annoying to the point of almost being a showstopper, ie. a reason not to use Opera. It's not only because I sometimes prefer to navigate the web using a custom UA string, it is a general concern:
Without this option there is no way any serious web developer can test the response of their sites to common scrapers and "search engines" and other bad bots using the Opera browser. Also, there is no way to test special content generation and logic for cell phones, web tv etc.
Also, for privacy/safety your browser UA string will often be a very good help in establishing a unique ID that may identify you across sessions and beyond cookie life span. Coupled with IP this is often enough. So, for that reason a "special" UA string is not desirable.
To top this off Opera only has two pre-configured user-agent strings (specific versions of IE + Explorer). However, unless you make an edit in an arcane text file these two UA strings will include the text "Opera", so that it's obvious to anyone that this is a spoof. How ridiculous is that?
Now, the worst part is that you need to set the UA string on a site-per-site basis. So, you have to navigate to e.g. Google using your default UA string. Then you have to make a site-specific rule for "google.com"... and even then - when you visit "google.co.uk" or any other Google site Opera will revert to your default UA string. (Google is just an example here - there are multiple other sites with more than one top level domain)
And, there is no way to change this; not even in configuration text-files or by making user scripts. You need to hack Opera itself in order to do it.
This is so stupid it hurts. It's really utterly ridiculous.
Feature request / What they should have done in stead:
IMHO, the only sane way to do this is to make it possible for the user to specify the *whole and exact* UA string permanently - that is, keep the setting you choose until you change it again. Regardless of which sites you visit.