A11y Buttons

To avoid conflicts that could break the editor experience, we opted to make the buttons interactive only on the published page, that is, outside the editor. This is valid for all the buttons, except for the Skip to link.

This plugin uses a strategy of updating the HTML root font-size only. This means that your fonts will only respond to changes if they are set in CSS relative units, such as rem. Other plugins achieve scaling by an "opinionated" strategy of setting different font sizes to different elements in the inner HTML tags. While we would recommend you to work with relative units, we also believe it is valid to discuss that...

This is a valid discussion as nowadays, each Browser dedicated Zoom feature can handle scaling much better, no matter which CSS unit you are using. Often, if your site has decent mobile responsiveness, its layout will be nice in a Browser-zoomed scenario. However, one can argue that the fact that everything is scaled (including images) pollutes much of the relevant, readable content. In the end, it is a topic that we are not 100% sure about and would love to find more research related to it.

Skip links should use HTML anchor navigation, which is done via IDs. If the ID is not set in the code, you can configure it via a block. To set an anchor to a search bar, for example, select its block in the site editor and scroll to the Advanced section in the block settings tab. Most blocks have an area there to define an anchor. You can then define it as search-bar-area and then type #search-bar-area as your link in the button block settings.

Internally, the Skip to link button is an anchor (<a>) tag, as its role is related to navigation. The other ones are actual <button> tags as they perform actions and not as linking. You may use the block formatting and settings to make them similar to each other.

The plugin keeps track of font-size and contrast toggle state preferences across pages using sessionStorage. Make sure to warn your users if you feel that can be sensible.

Originally, we planned to have a simple feature to add accesskey to each button. After reading this, we gave up.

Yes! If you have an image like a monochromatic logo that would make sense to be inverted, add the class a11y-invert-on-contrast-mode to it so it can be inverted.

I know, it is a bit confusing and advanced topic. If you keep the default ("On-Demand Loading"), a small JS script will always be loaded in your website. This script will be responsible for detecting the presence of A11Y Buttons, add interactivity for them and, when needed, enqueue CSS assets like the ones used by High Contrast and Readable Font buttons. The idea is that the style is only inserted in the HTML header if the button is clicked. It also works if you used not the Gutenberg block but a simple HTML markup to mimic the block. However, this has a performance issue: the CSS are not cacheable. By using the second option ("Block Detection Loading") we leverage the entire assets enqueue job to WordPress. If it detects a buttons block in that page it will load both the JS script and the CSS files. This allow them to be cacheable. The disadvantage is that all CSS will be loaded even if a certain button is not used... but keep in mind that they are really small. This also won't work for the rare scenarios where you are building your HTML markup by hand instead of using blocks.