Images missing width and height
What this means
More than three images on the page declare no width and height attributes, so the browser cannot reserve space for them and content shifts as they load.
How to fix it
Add explicit width and height (or a CSS aspect-ratio) to every img element so its box is known before the file arrives.
Fix effort
This check needs review: the change can be drafted for you, but a person has to approve the wording or choose the target before it ships.
Authoritative source
https://developers.google.com/search/docs/appearance/google-images
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