One of our on-line document management sites has sent us a mail like this:
It has come to our attention that certain users are still using older browsers while trying to use ******, and are therefore experiencing problems out of our control. ****** has been programmed to only work on the latest browsers, and therefore Internet Explorer 7, 8 and 9 are included in the list of out-dated browsers.
So no XP, and only IE10 (or later). Though fortunately they do state this later in that same email:
We recommend downloading Google Chrome as many of the features that make your ******* experience easier, are already built into Google Chrome.
No mention of FF or Opera though, never mind Safari.

Sorry to ask, but my web programming is a bit dusty. Is IE still in the same old boat - severe incompatibilities between versions?