Can the cobrowse.js script be loaded in a deferred fashion on the client side: So either put JS at the end of the page instead of in the head or add below defer attribute in script tag? <script defer="true" src="..." /> We have seen that cobrowse JS takes significant amount of blocking time (100 ms - 300 ms) when being loaded on client browser. Hence would like to defer the script load towards the end to not block other traffic on the website.