Possible bug: X-UA-Compatible differs from Compatibility View

Just encountered a behaviour in IE8 that could be considered a bug.

I've got a page which renders X (to make it abstract) in IE8 on one PC and
renders Y on another PC.
The page contains the X-UA-Compatible tag, so you would think that it's not
an IE8 problem, but something different.
After digging - the website was in the Compatibilty View list on one PC and
not on the other.
Adding the X-UA-Compatible tag to the page (and the whole site actually)
hides the button to turn on/off the Compatibility View next to the refresh
button. It has to be done through the menu, but no normal user does that I
guess, only developers.
So if you turned on Compatibility View before the meta tag was added, you
get different rendering compared to never having turned on Compatibility View.

I was to believe that the meta tag forced the Compatibility View, but
apparently it does something else here.

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Hi deef,

It also depends on the DocType schema chosen by the web developers.

The X-UA flag can also be set in the response headers. Also see
"Automatically recover from rendering errors with Compatibility View" on the
Advanced tab of Internet Options.

Regards.

"deef" <deef@discussions.microsoft.com> wrote in message
news:38F9AA40-C407-462D-AF0E-5A6AB26243EE@microsoft.com...
> Just encountered a behaviour in IE8 that could be considered a bug.
>
> I've got a page which renders X (to make it abstract) in IE8 on one PC and
> renders Y on another PC.
> The page contains the X-UA-Compatible tag, so you would think that it's
> not
> an IE8 problem, but something different.
> After digging - the website was in the Compatibilty View list on one PC
> and
> not on the other.
> Adding the X-UA-Compatible tag to the page (and the whole site actually)
> hides the button to turn on/off the Compatibility View next to the refresh
> button. It has to be done through the menu, but no normal user does that I
> guess, only developers.
> So if you turned on Compatibility View before the meta tag was added, you
> get different rendering compared to never having turned on Compatibility
> View.
>
> I was to believe that the meta tag forced the Compatibility View, but
> apparently it does something else here.
>
> ----------------
> This post is a suggestion for Microsoft, and Microsoft responds to the
> suggestions with the most votes. To vote for this suggestion, click the "I
> Agree" button in the message pane. If you do not see the button, follow
> this
> link to open the suggestion in the Microsoft Web-based Newsreader and then
> click "I Agree" in the message pane.
>
> http://www.microsoft.com/communities...orer. general
>