There was a major change (Glitch) to what buttons did while looking at containers (prior to entering the transfer menu) at least if you have a custom button setup. In simple terms it appears that whatever your custom;

"Activate" button is set to is now your "Take" button while looking at containers (before accessing them in transfer menu)
"Reload" button is set to is now your "Transfer" button while looking at containers (leads to normal transfer menu in which all buttons revert to normal (desired) settings "A" to take and "X" to transfer/take all)

This wouldn't be a huge issue if it wasn't contradictory to every other menu in the game (workbench, trade, transfer, buy, etc...) and that it was default menu access to all of these prior to the un-voluntary patch (that is to say "A" to take and "X" to transfer/take all which is how I liked it and was accustomed to it and considering I have done take all on EVERY enemy in EVERY Bethesda game prior to this that I played that I killed as I killed it... (that is a lot of habit forming activity to break - [informative]) so now mid combat I have to actually look at the menu and remember the buttons have changed (but only for the looking at container menu so it flip flops once you hit "B" to transfer) after.. years of playing these games.. this is a MAJOR annoyance). Now after over 12 days of in game experience pressing the default menu buttons I keep grabbing things off my chests that I don't want to grab and short of remapping those buttons to default I have no recourse. Can't wait to try this in combat since I'm playing on survival mode and those kinds of mistakes = death [fear/trepidation].

Help Bethesda?

Maybe next update you could force us all to play legacy control style?[Sarcasm] (kidding... but it would be pretty funny for a little while)

Console - Xbox One (in case anyone asks, although I believe I am posting under the Xbox One Section of the Forum )

Bethesda Games Owned/Played
Oblivion on Xbox 360 two copies (One with expansions and One GOTY edition)
Fallout 3 Xbox 360 two copies (One with expansions, and one GOTY edition), PC One Copy
Fallout 3 New Vegas Xbox 360 two copies I think both GOTY edition, PC One Copy
Skyrim Xbox 360 two copies, Skyrim PC one copy
Bethesda - Creation Kit, two copies on PC. Not a game? I beg to differ!
ESO Xbox 360 one copy... meh.
Fallout 4 Xbox one, one copy... so far lol.