Accessibility: Cross-Browser Tab Order Inconsistency

The Problem

Keyboard navigation order behaved inconsistently across browsers, with key interactive elements appearing in different positions within the tab sequence.

In Chrome, the "Skip to Main Content" button appeared at the beginning of the tab order as expected, but in Firefox it appeared at the end, breaking expected accessibility behavior.

What I Did

Investigated differences in how browsers calculate tab order, focusing on DOM structure, focusable elements, and implicit tab indexing.

Identified that DOM order and rendering structure within the header component caused Firefox to evaluate focus order differently than Chrome.

Refactored the component structure to ensure the skip navigation button appeared earlier in the DOM, aligning browser behavior.

Validated the fix using keyboard-only navigation across multiple browsers to confirm consistent tab sequencing.

• Performed a detailed cross-browser analysis of keyboard navigation behavior, identifying discrepancies in how tab order was calculated between browsers. The issue was traced to DOM structure and focus evaluation differences, particularly within the header component. The solution involved restructuring the DOM to ensure the "Skip to Main Content" button appeared first in the document flow, allowing both Chrome and Firefox to interpret the tab order consistently. Additional validation was performed using keyboard navigation testing to confirm correct behavior across environments.

Outcome

• Ensured consistent keyboard navigation across major browsers
• Improved accessibility compliance for assistive technology users
• Reduced friction for keyboard-only navigation
• Increased confidence in cross-browser UI behavior