PROBLEM DESCRIPTION or QUESTION
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Xterm copies text just by dragging the mouse and pates it using the mouse middle button. How can I do that with Xshell?
RESOLUTION
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You can change the role of the mouse buttons in the global options.
Check 'Copy selected texts to the clipboard automatically' for automacitally copying texts
Select 'Paste the clipboard contents' as the Middle button action for pasting the copied texts.