We frequently use this web part because it allows us to control the sequence of loading scripts on the master page template and standard page template control hierarchy when doing Kentico Portal Engine development. Side note: yes, all you Kentico MVC developers out there aren't going to learn too much from this post, deal with it, I gave you some love in the last Kentico Rocks podcast episode already.
Whenever you add this web part to a page template, and configure it to use a library script, or create your inline script, it will nicely render that script out to your page(s). It's pretty straightforward really.
When we tested out the pages, everything worked great. The social buttons popped up, we tested the sharing out, and even had our custom open graph meta data tags working to pre-populate the title, description, and image properties for Twitter, Facebook, etc. etc.. The code was committed to source control, it passed QA, the client ran through acceptance testing, and the feature went live. People cheered, seas parted... ok that last part didn't really happen.
As you can see, the exception generated was not something we were expecting for a client side change, especially since we un-checked the Generate script tags attribute..
Solution: Remove the comments!
In my limited testing, this issue does seem to be resolved in the newest version of Kentico 9.0. So hey if anything, consider this blog post as another reason to upgrade to the latest version of Kentico 9. Especially since Kentico 10 is right around the corner ...hopefully.
I hope that this quick tip saves at least one Kentico developer out there a head scratching moment. I know that we were sure puzzled for a few minutes on it. Now my team's conversation has changed to how do we prevent this in the future. Automated regression testing was once solution thrown out there, sometimes that's possible, and sometimes not depending on your client's budget. I would be interested to hear if anyone else out there has ran into this issue. If you have leave a comment at the bottom of the page. Thanks!