What does browser.bootstrap stand for in dukescript projects? -

every time generate new dukescript project using knockoutjs sample code, appears in comment: browser.bootstrap

<!-- ${browser.bootstrap} --> 

does have use? necessary?

it has use. it's placeholder. if wan run project in browser teavm or bck2brwsr required javascript code injected here. in other projects doesn't anything. if remove it, project won't run in browser.