I know that there is an add on with firefox if you middle click you can open a shop item in a new tab.

I can't tell what you are asking here. Did your question get accidentally edited out?

no it didnt get edited out but i did figure it out. there is an Add On called Tab submit, and that allows you to middle click (clicking with scroll wheel) on a main shop item, to open it in a new tab. So if you wanted to open multiple items in a main shop you have that option

ctrl + left mouse button has the same effect =|

thank you BUT when trying to buy super rare items in the shop I prefer to keep my left hand on the number keys at the top to reduce that fraction of second delay XD