How to use set up middle click for "Paste" action in Linux

Problem

I use the middle click for the "Paste" action in Linux

In IntelliJ Terminal, this works. In IntelliJ Editor, this does not work

Cause

On Linux, there are two types of clipboard: "Primary Selection" and "Clipboard Buffer" (description). Selected text goes to Primary Selection after you finished selecting. When you press Ctrl+C, it goes to Clipboard Buffer.

On Linux, when you click the middle mouse button, the content from the primary selection is pasted. When you press Ctrl+V, the content from the clipboard buffer is pasted.

Solution

Set up the keymap as shown:

1. Go to "Settings | Keymap"
2. Find action "Paste" (in the group "Editor actions")
3. Right-click on it to add "Mouse action"
4. Middle-click
5. Save