I just added a Google Tag Manager script to a client site which is running Kentico 7. I added the code to the master template directly so that I could place it immediately after the opening HTML body tag, per Google's recommendation. After doing so, the WYSIWYG toolbar in the Kentico CMS Desk no longer appears. I tried moving the GTM code to the HTML head, but it produced the same results. Removing the script immediately returned the toolbar to it's working state. Any ideas?
Call me crazy, but did you make sure that the code you pasted included a closing /script tag?
Just an idea...
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