Images spill over into sidebar with Twenty Ten theme

There’s no defect. Every theme specifies a set of thumbnail images to be generated when you upload an image, and these different image sizes are used at various sections of your website.

So when you switch themes, you’ll end up with existing thumbnail image sizes (specified by the old theme) that may not be optimized for the new theme.

The recommended solution to this is to use a plugin to regenerate new thumbnails optimized for the new theme.

For your specific issue of preventing images from extending outside the content area, head over to APPEARANCE => CUSTOMIZE => ADDITIONAL CSS, and put in the following:

.entry-content img {
    max-width: 100%;

Thank you for the elegant and effective solution to my problem.


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