Provided by: rxvt-unicode-256color_9.19-1_amd64 bug

NAME

       selection-popup - (enabled by default)

DESCRIPTION

       Binds a popup menu to Ctrl-Button3 that lets you convert the selection text into various
       other formats/action (such as uri unescaping, perl evaluation, web-browser starting etc.),
       depending on content.

       Other extensions can extend this popup menu by pushing a code reference onto "@{
       $term->{selection_popup_hook} }", which gets called whenever the popup is being displayed.

       Its sole argument is the popup menu, which can be modified. The selection is in $_, which
       can be used to decide whether to add something or not.  It should either return nothing or
       a string and a code reference. The string will be used as button text and the code
       reference will be called when the button gets activated and should transform $_.

       The following will add an entry "a to b" that transforms all "a"s in the selection to
       "b"s, but only if the selection currently contains any "a"s:

          push @{ $self->{term}{selection_popup_hook} }, sub {
             /a/ ? ("a to b" => sub { s/a/b/g }
                 : ()
          };