Interesting phenomena in Opera

Just wanting to hear some opinions on this interesting phenomena I was recently made aware of using Opera and what I should do as a webmaster to avoid spooky values being added to my forms.

Find a page that has a form that has a drop down list.
Normally you can’t enter a value into the drop down list.

What happens for you if you do the following:

FILE | WORK OFFLINE

Right click in the page. FRAME | VIEW SOURCE

When you have the HTML up, change the value of the SELECTED option and the text that accompanies the selected option.
eg.
<option selected value=‘This is a test’>This is a test<option>

SAVE the file.

CLOSE the file.

Go back to Opera, hit REFRESH.

FILE | WORK OFFLINE make sure it’s UNTICKED.

SUBMIT the form.

As far as I have been able to test here, that value you just entered should be sent through on the form.

I think (personally) I’m going to have to go back through my sites and validate each of the values in the drop down list to make sure they match one that I expect to be there.

Does this happen for you?

Is this bizzare?

Should this be happening or is it something that the Opera people should / do know about?

Your opinions will be valued.