How can I ascertain what browser and document mode my DOCTYPE and metadata is pushing?

3
votes

So I have a document that has some display issues, when in compatibility view in IE8, 9, 10. It has the following DOCTYPE:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

There is no other metadata in the head.

Now, when I load the page in any of the above versions, the page renders in non-compatibility mode, and displays correctly. But I have other users who are reporting that the page opens in compability mode, and thus displays incorrectly. The problem I have is I can't tell:

  • What this particular DOCTYPE will tell the browser to do

  • If my F12 Dev settings have been manually set to non-compatibility mode so it's ignoring the document

  • If my user's F12 dev settings have been manually set to compatibility mode so it's ignoring the document

So I guess what I need here is to know:

  • What mode the above DOCTYPE, with no other metadata, will ask the above browsers to do by default

  • Do changes to the Browser or Document modes in F12 Developer Tools persist over multiple sessions of the browser (such that myself, or my users could be overriding the document)?

  • What DOCTYPE and metadata I should put in my document to ensure that compatibility mode is not engaged by the above browsers? My understanding from MSDN documentation is that <!DOCTYPE html> is sufficient?

1
htmlinternet-explorercompatibilitydoctype
You know the user can manually put their site into compatibility mode and there is nothing you can do about it, right? The button is also very easy to press by accident. God I hate IE..... - Liam
The doctype itself, does not say, use compatibility mode. The doctype says, this is a dtd that defines what my content is. So you can't necessarily say x doctype will trigger compatibility mode in y browser. It's subjective and, like I say above, the user can simply override it anyway. Your best bet, though this isn't as easy as it sounds, is to create a website that works in compatibility mode. Incidentally <!DOCTYPE html> is the HTML5 doctype. - Liam
Understood, although I was of the understanding that IE 8-10 will respond to a DTD in a particular, deterministic way. I need to be able to verify that, in the above case, IE isn't slipping into compatibility mode by default, and simply that my users have compatibility mode on of their own accord (and I suspect it's more likely that I have it set to something, rather than they). - njp
Be careful not to confuse compatibility mode with quirks mode. The doctype is only relevant to whether the browser goes into quirks mode, not compatibility mode. - Spudley
The question is too broad and based on incorrect assumption. The construct given at the start of the question is not a doctype at all; it is simply a comment. - Jukka K. Korpela

1 Answers

2
votes

You can always use

<meta http-equiv="X-UA-Compatible" content="IE=edge" />

which will force IE to put itself in "non compatibility mode" worth a try.