Why it matters
Screen readers announce an iframe by its title. Without one, users hear only "frame" and cannot tell a video, map or ad apart from content.
How to fix it
Add a short title that describes the embedded content.
Example
<iframe src="https://www.youtube-nocookie.com/embed/…" title="Product demo video"></iframe>References
More accessibility rules
void a11y reports 48 rules in this category. WCAG 2.2 AA through axe-core, plus checks axe can't do alone: visible keyboard focus, 24/44px target size on mobile, 320px reflow and disabled zoom.
aria-toggle-field-nameARIA toggle has no accessible namearia-prohibited-attrARIA attribute is prohibited for this rolenested-interactiveInteractive controls are nestedduplicate-id-ariaDuplicate id referenced by ARIAsvg-img-altSVG image has no text alternativerole-img-altrole="img" element has no text alternativetabindexPositive tabindexscrollable-region-focusableScrollable region is not keyboard accessible