Angular 2 app loading slow in Firefox

I've used Chrome for development and app always has loaded fast there. But now I tried to run in on firefox and it takes about 8 seconds to load with horrible pauses and even a preloader at place of favicon stops for some moments during loading process. I've recorded the loading process with performance mozila tool and got multiple calls of globalZoneAwareCallback, GC calls and multiple of style recalculations. I got almost the same picture in my chrome browser except for style to not recompile that much, but why it's so faster here than in firefox? Is it because of styles? How can I fix performance of loading in mozila?