fullscreen_this.md
In shinyfullscreen: Display 'HTML' Elements on Full Screen in 'Shiny' Apps

fullscreen_this produces the right JS

[1] "<div id=\"plot\" class=\"shiny-plot-output\" style=\"width: 100% ; height: 400px\"></div><script> $(function () { if (!screenfull.isEnabled) { return false; } $('#plot').click(function () { screenfull.request($('#plot')[0]); }); });</script><style>#plot{ cursor: -webkit-zoom-in; cursor: -moz-zoom-in; } ::backdrop { background-color:#fff; }</style>"

argument click_id works

[1] "<div id=\"plot\" class=\"shiny-plot-output\" style=\"width: 100% ; height: 400px\"></div><script> $(function () { if (!screenfull.isEnabled) { return false; } $('#other_id').click(function () { screenfull.request($('#plot')[0]); }); });</script><style>#plot{ cursor: -webkit-zoom-in; cursor: -moz-zoom-in; } ::backdrop { background-color:#fff; }</style>"

argument bg_color works

[1] "<div id=\"plot\" class=\"shiny-plot-output\" style=\"width: 100% ; height: 400px\"></div><script> $(function () { if (!screenfull.isEnabled) { return false; } $('#plot').click(function () { screenfull.request($('#plot')[0]); }); });</script><style>#plot{ cursor: -webkit-zoom-in; cursor: -moz-zoom-in; } ::backdrop { background-color:pink; }</style>"