Before creating your own accessibility widget or overlay, consider the following:
Avoid Duplicating Native Features: Most operating systems and browsers already include robust accessibility tools (e.g., screen readers, zoom, and high-contrast modes). Instead of replicating these, focus on ensuring your website or app is compatible with them.
Keep It Simple: If you decide to implement an accessibility widget, make it lightweight and focused. For instance: Add a font size adjustment option, include a toggle for high contrast or grayscale mode, Provide simple keyboard shortcuts for toggling features.
Open Source Integration: Leverage existing tools, such as libraries like Ranbuch Accessibility, to save development time and adhere to best practices. These libraries are designed to offer simple, configurable widgets.
Challenges of Overlays: Accessibility overlays / widgets are often criticized by the accessibility community for not addressing the root accessibility issues. Instead of using an overlay to 'fix' issues, ensure your HTML structure, ARIA roles, and WCAG compliance are solid from the ground up.
Implementation Tip: If you build a widget, make it complementary and transparent. For example, don’t interfere with assistive technologies, but rather offer additional convenience features for users.