Success Criterion 1.4.10
Conformance level AA
W3C reference F102

Content or Controls That Vanish Entirely When the Page Reflows

1.4.10 — Reflow

Scenario

Setting

A social media platform's settings menu

What’s wrong

When the page reflows at small width / high zoom, some content or controls simply disappear with no other way to reach them.

Example

.layout { width: 1200px; }

Why it matters

Low-vision users at high zoom and people reading on narrow mobile viewports.

How to test

Set the viewport to 320 CSS px wide (or zoom desktop to 400%): scroll only vertically and check that no content or controls have vanished compared to the normal view.

How to fix

Keep all content and controls available at 320px — reflow, stack, or provide an accessible alternative path. .layout { max-width: 1200px; width: 100%; } Content must reflow into one column at 320px wide with no horizontal scrolling and nothing missing.

Outcome

On a social media platform's settings menu, this barrier is gone for low-vision users at high zoom and people reading on narrow mobile viewports — they no longer have to work around this.

Who is affected