The print button on the My Feedback report has an off-white background on some themes.
 
Removing the below css, which adds an info icon, but also changes the background of the button to a pale colour fixes the problem.
.path-report-myfeedback #reportPrint {
 
       background: #f5f5f5 url(/report/myfeedback/pix/info.png) right center no-repeat;
}