Just noticed it yesterday; thought it be a shadow, but now I know it is a slight, but significant, bulge in the middle of the outside of the door.
Answers: About the one and only way I know that you can acquire a bulge is if the insulation has shifted of if it have gotten wet and froze. You would involve to dissemble the for to know for sure. First step would be to push gently on the bulge and see if it have any give to it. If it does you may freshly need to re-glue the door panel pay for together internally.
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