Images must have alternative text
Moderateimage-alt
What it checks
Ensure <img> elements have alternative text or a role of none or presentation
How to fix it
Add descriptive alt text to all images that convey information
WCAG
Success criteria 1.1.1. See the WCAG 2.2 quick reference.
An example of the problem
<img src="/a.png">More detail: Deque University's page on this rule.