I am trying to understand how GTM works. Having inserted the container code to my page, I created two tags, "Custom HTML Tag" and "Custom Image Tag" and published them. In the "Custom HTML Tag", I wrote:
In the "Custom Image Tag", I set the image URL.
You can see this HTML page I use to conduct this test: http://www.xrsand.com/word2html.html. Now there are several problems I think are critical in order to further understand how GTM works:
Turns out the codes in "Custom HTML tag" are inserted into the page before the closing
bodytag, but the "Custom Image Tag" is not. So what is this "custom Image Tag" supposed to do?
In Chrome only, a tag manager iframe appears.
This won't appear in other browsers. Why? And I don't think regular users are supposed to see this iframe. How to turn it off?