Provided by: rxvt-unicode_9.22-6build3_amd64 
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NAME
selection-to-clipboard - copy the selection to the clipboard each time a selection is made
SYNOPSIS
urxvt -pe selection-to-clipboard
DESCRIPTION
This very simple extension copies the selection to the clipboard every time a selection is made. This, in effect, synchronises the clipboard with the selection for selections done by rxvt-unicode.