This is not something that has been included in this week’s 6.0 release, so in that particular regard upgrading will not help you. Proofreading is still pretty neat though 
. Whether or not this will be in a subsequent 6.x release is anyone’s guess, although I suspect it is indeed quite niche while requiring considerable programming effort (i.e. nope). But the developers take note of every request here, so by all means add your voice to the pile.
In the replies to my original FR you can find a workaround to follow, but as such it is rather fiddly.