Animation preview functionality breaks code

Hi!

Does anyone have a suggestion why Animate cc places a random number behind .js file in the published html, while previewing the animation (via ctrl+Enter). Is this unavoidable when trying to refresh/update the browser?  When publishing for google display ads, this shows up as an error. I know, a disciplined person would always push "publish" before sending files off to google but when you have "and then some" number banners to make this becomes a major annoyance and a time waste as some usually slip trough. Has anyone seen this as a problem? Quick rummage through this forum did not yield any results for me .

Silver