The simple answer is: No, Justuno does not slow down your load speeds.
Justuno uses an asynchronous technique to load our widget. This means it does not block the loading of other content on your website. Therefore should not affect the speed.
If you still suspect Justuno is slowing your page load, use the Developer Tools built into your web browser to measure the network timeline. Some online tools do not take into account the polling Justuno will periodically initiate a customer profile update after the page has finished loading, making the page load appear slower on these tools. This is false information because it's not slowing down your site's initial page load.
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TAGS: affecting load time, load time, website slow down