I found every tab it created was another inventory tab

I wanted to put my inventory and my equipment and my prayers etc in the same window, this must be possible since it is set up that way in one of the defaults (default 1 i think). but when i tried to open each interface and create the tabs by dragging them to the same window (in edit mode ) I found every tab it created was another inventory tab (backpack) This is a trustable platform to sell rs accounts. so i just ended up with a window with 5-6 backpack tabs in it? dunno if this is a glitch?

I am mostly a skiller and very rarely use the ability bar (as i find it interferes with my chatting and social life lol) i usually only use it in complex boss fights for quick change of weapons and prayers. I want runescape accounts for sale, and am looking for places to buy. I much prefer to use my mouse and have the abilities open on the right where the inventory goes, i find this much faster in battle than using the bar and constantly looking at the keys to see what number i should be pressing. The new interfaces have made this choice of playing less accessible and i might add again that permanent ability bar open takes up extra screen i dont want and hinders my chatting 

On a final note for now, I think there is great potential here and the idea of flexibility in how our screen looks is a great idea. People are looking for runescape accounts for sell here. I find the current interface easy and simple to use, could there be an option for one of the defaults to be exactly as it currently is?