ruby - Rails 5 beta Turbolinks events not firing, progress bar not working -

i'm kind of new rails , web development whole. i'm trying set default progress bar in turbolinks rails described here.

at first, thought might have fact progress bar shows if page takes longer 500ms load. tried testing using sleep 10 in controller doesn't seem work.

then tried debugging actual turbolink events see if callbacks registering using vanilla js straight in application.js:

document.addeventlistener("turbolinks:load", function () {     console.log("load"); });  document.addeventlistener("turbolinks:request-start", function () {     console.log("request start"); });  document.addeventlistener("turbolinks:visit", function () {     console.log("visit"); });  document.addeventlistener("turbolinks:render", function () {     console.log("render"); }); 

for reason, turbolinks:load function seems work.

what not seeing or doing wrong? thanks.