Width and height attributes on image tags tell the browser how much space to reserve for each image before it has finished downloading.
Why this matters
Without these attributes, the browser cannot reserve the correct space, so the page layout shifts as images load, causing text and buttons to jump around. This is measured as CLS (Cumulative Layout Shift), one of Google's Core Web Vitals, and missing image dimensions are a common cause of poor CLS scores.
How to fix it
Add explicit width and height attributes to every image tag on your site. These should match the image's natural dimensions; CSS can still be used to make it responsive.
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