The theme is 1140px by default now. It’s a little wider than before (960px). So you can use a plugin called Regenerate thumbnails and it will automatically adjust all of your images to fit. But first change the size to 1140px width and adjust the height to whatever size you want.
Most people prefer a wider sized theme, that’s why the update added that. If you don’t want the 1140px width and would rather go back to the 960px width then you can make this adjustment in the css….but let me know first and I’ll tell you what to do if you want.
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