Hi everyone,
Just to clarify this, I’m afraid that in dropping IE8 browser support, we are also dropping the IE8 “compatibility view” in any browser. Unfortunately, the way compatibility view is implemented it not only maintains old and non-standard features that IE8 supported, but also omits the new JavaScript functionality from ECMAScript 5 that was implemented in IE9. In terms of of testing and maintenance cost, it is a whole different browser, and not one we can justify supporting any more.
For modern applications which you control, you should be able to fix the mode of the browser (regardless of default policy) with <meta http-equiv="X-UA-Compatible" content="IE=edge">, or another specific, post-IE8 browser version.
Ben