This is a fan continuation of the out-of-date Stackpack addon by Djuice, updated to work for Battle for Azeroth and beyond. I've revived the addon with Djuice's permission. As of 2024, supports the latest Dragonflight Retail as well as Classic Era and Wrath Classic versions.
Stackpack automatically stacks together any stackable items in your inventory by moving items or smaller stacks onto the largest stack until the stack size limit is reached. Unlike the builtin Cleanup button or other addons, there's no need to click any button or use any slash-command to do this stacking—it happens on its own. And it doesn't reshuffle your inventory around, other than stacking stackables, so your bag organization method (if any) is not affected by using Stackpack.
Stackpack also automatically works within your bank bags and reagent bank.
By default it also works within guild bank tabs (can be disabled with /stackguild off), and adds a "Stack Entire Bank" button to the guild bank frame.
Stackpack can also add itemIDs, Item Levels, and Stack Sizes to tooltips, and provide filterable inventory/bag/bank/gbank searching.
For more info on searching and available commands/options: /stackpack help
The following description is from the original addon page ...
What is Stackpack?
Have you ever had to destroy an item just to free up space, only to find out that you could've combined 2 or more stacks of the same item? What about that tradeskill item you could've moved into your tradeskill bag to free up space? Stackpack searches each of your bags to stack items together and move tradeskill and specialty items where they belong.
What else can it do?
Ever looked through your bank for what seems like an eternity, repeatedly overlooking an item that you KNOW is there? Stackpack brings a powerful search to your inventory, personal bank and guild bank windows, allowing you to quickly find what you're looking for. It supports a number of filters that allow you to find items based on certain characteristics.. such as Soulbound, Bind on Equip, Weapons or even Junk items to vendor.
What about the bank?
Stackpack will stack your items in the bank as well, and ignores any changes to your normal bags so you can easily split and add partial stacks to your bank slots as you please. Additionally, Stackpack fully supports users of all inventory management addons.
What if I don't want to stack temporarily?
Stackpack will toggle itself off automatically when you split a stack of items. You can also bind a key to temporarily disable Stackpack (which will re-enable itself automatically after the next inventory change) or you can use the /stp toggle command. To turn Stackpack off permanently, you can use the /stp off command. Using /stp on will turn it back on.
Do I have to do that every time I trade?
Nope. Stackpack will not stack items while the trade window is open.
What about sending mail?
Stackpack will not stack items while the send mail window is open, making it easy to split and send partial stacks as you please. Stackpack will resume stacking when the read mail window is open, or when the mail frame is closed altogether.
Please use the curseforge ticketing system for any problems/feature requests/comments you have about this addon.
I use the addon myself and like to have it functional, but I'm not its original author and may not necessarily be able to fix or update it quickly, so please be patient.