Nice screenshot: http://imgur.com/bw8wQGu
Tried with all AE2 version (AE2 rv2 stable 1)
Baiscly the player inventory is double added, this can cause dupes and more.
Can be fixed with #1443
@TheJulianJES confirmed like you said, luckily I was not able yet to find a way of duping anything in survival (not to say it isn't possible with this bug) which is a good thing :)
@Ianaver Good, I think duping with Inventory Tweaks COULD be possible but I'm not sure.
What am I seeing? Whiter inventory highlight thus double player inventory?