Vimeo embed on webpage causes an error

I'm trying to troubleshoot a strange bug on one of our pages (https://www.bbg.org/visit/sakura_matsuri_photos). The bottom of left of the page has the text 'cp_vimeo_code.js Open' and I can't figure out what is generating this. here is what it looks like

I've noticed that there are other websites that show this error too, for example: https://www.indicia.nl/project/anderson-macgyver/.

I have the following three embeds inside the body tag of a webpage in Expression Engine. Taking them out eliminates the error.

<div class="videoWrapper">
<iframe src="https://player.vimeo.com/video/210978232?title=0&amp;byline=0&amp;portrait=0" width="540" height="304" frameborder="0"></iframe>
</div>

<div class="videoWrapper">
<iframe src="https://player.vimeo.com/video/210978156?title=0&amp;byline=0&amp;portrait=0" width="540" height="304" frameborder="0"></iframe>
</div>

<div class="videoWrapper">
<iframe src="https://player.vimeo.com/video/160249045?title=0&amp;byline=0&amp;portrait=0" width="540" height="304" frameborder="0"></iframe>
</div>

Has anyone seen something like this before? I can't find it on Vimeo's site anywhere. Here is a picture of the error on our page

I finally figured where this was coming from, it was some extra code in a Google Tag Manger custom tag!!