According to post from official blog of Internet Explorer team the only two ways to change compatibility mode of WebBrowser
control are:
- Add FEATURE_BROWSER_EMULATION key to the registry for your application
- Specify compatibility mode within HTML code of web page using !DOCTYPE and/or meta tags
Please note: Default mode of rendering pages by WebBrowser may depend on Internet Explorer version installed on machine, as it uses components of Internet Explorer. For IE8 by default WebBrowser
renders pages in IE7 standards mode.
Part of your application's pages may fall back to older mode (quirks mode) due to crash of more modern render (which in fact can differ from one that is used when page is opened directly in IE) caused by some content on the page.
To resolve described problem you can alter HTML code of corrupt pages with DocumentText property of WebBrowser
class in order to explicitly specify document compatibility that is appropriate for the pages (i.e. ensures proper rendering).