The alignment of the sticky table headers is out. I think it may be a difference in the width calculation due to shiny applying box-sizing: border-box.
What's the browser that you're using? Is there a screenshot or something? I can't replicate this.
Since it's been almost a year, I'm closing this.
I can confirm removing box-sizing: border-box; fixes the problem.
This problem is present in Firefox and Chromium browsers.
I think this is still happening, I am using Chrome 37.0.2062.124 on OS X 10.9.4, attached are two screenshots.
Text's in Spanish, but you'll probably get the effect anyway:
The non-admin theme is currently bootstrap, I am not sure if that's has anything to do with it.
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