TLDR; mouse chording is triggering custom actions (like copying text) by holding down a mouse button and then pressing another. This is best done with a three-button-mouse, where the middle button does not double as scroll wheel.

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I became aware of this when I discovered Acme, the text editor of plan9 - which uses mouse chording for a few things. This explanation of mouse chording in Acme is pretty good.

I found it very interesting and wanted this to work system wide on my computer.

After some hacking in AutoHotKey I got the following setup to work:

• Left + Middle = copy
• Left + Right = paste
• Right + Left = undo
• Right + Middle = redo
• Middle + Left = enter
• Middle + Right = space
• Middle + Scroll = switch app (Alt+Tab)

I find this very useful, and it saves me from needing to switch back and forth between the keyboard and mouse all the time, which is annoying.

I can also be productive while using only the mouse - especially for simple tasks like data entry; copying text fields, one by one, from one window to another.

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To do this effectively, one really needs a three button mouse, often referred to as “CAD mouse” (because of some software called CAD that requires this).

Mice like this are kind of rare, but I eventually found this, which is what I currently use: https://www.amazon.co.jp/-/en/Shengshou-Buttons-Scroll-Wireless-Suitable/dp/B0832BBY8Y/

I really like how the scroll wheel is on the side and out of the way of the buttons.

This one is more or less the same, but with the scroll wheel between the left and middle button: https://www.amazon.co.jp/-/en/Wireless-Rechargeable-Precision-Portable-Defining/dp/B087TFLVPJ/

This seems to be the perfect mouse for chording, but It’s a little expensive: https://www.amazon.com/3DConnexion-CadMouse-Pro-Mouse-Optical/dp/B08R5KS38N/

I’ll probably get one eventually, since it has back and forward buttons which I can use to add even more custom chordings.

Anyone else into mouse button chording? Any other good mice for this?