find_all_formula_fields.js

var jq = document.createElement('script');
jq.src = "//ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js";
document.getElementsByTagName('head')[0].appendChild(jq);

function main(){
    var formulaFieldCells = $("td:contains('Formula (')");

    var fieldList = [];
    formulaFieldCells.each(function(){
        formulaField = $($(this).prev()[0]).html();
        if (formulaField.indexOf('__c') != -1){
        	fieldList.push(formulaField);
        }
    });

    console.log(fieldList);
}
setTimeout(main, 3000);