* `attributeChangedCallback` processes changes to the `expanded` attribute.

* `attributeChangedCallback()` is called when any of the attributes in the * `observedAttributes` array are changed. It's a good place to handle

* Properties and their corresponding attributes should mirror one another. * To this effect, the property setter for `selected` handles truthy/fa

* `attributeChangedCallback()` is called when any of the attributes in the * `observedAttributes` array are changed. It's a good place to handle

* `browserFilter` is used as an argument to `Array.prototype.filter` to filter * which browsers are used to run the e2e tests.

* Properties and their corresponding attributes should mirror one another. * The property setter for `checked` handles truthy/falsy values and

* A getter for whichever `HowtoRadioButton` is currently checked.

* `connectedCallback` hooks up the even listeners and considers the * `expanded` attribute on the headers to adjust their styling accordingly.

* `connectedCallback()` sets up the role, event handler and initial state.

* `connectedCallback()` sets up the role and the ID of the element.

* `connectedCallback()` fires when the element is inserted into the DOM. * It's a good place to set the initial `role`, `tabindex`, internal state,

* `connectedCallback()` fires when the element is inserted into the DOM. * It's a good place to set the initial `role`, `tabindex`, internal stat

* `connectedCallback()` groups tabs and panels by reordering and makes sure * exactly one tab is active.

* connectedCallback() will run once the element is attached to the document. * It's the earliest point at which you may touch attributes, and is

* `connectedCallback()` fires when the element is inserted into the DOM. * It's a good place to set the initial `role`, `tabindex`, internal stat

* The `HowtoRadioButton` sets its initial ARIA attributes when it's * attached to the DOM. The surrounding RadioGroup handles dynamic changes

* The `HowtoRadioGroup` sets its ARIA role to `radiogroup` and sets the * `tabindex` on its first `HowtoRadioButton` child to 0 if no other child

* The constructor does work that needs to be executed _exactly_ once.

* The element's constructor is run anytime a new instance is created. * Instances are created either by parsing HTML, calling * document.cre

* The element's constructor is run anytime a new instance is created. * Instances are created either by parsing HTML, calling * document.cre

* `disconnectedCallback` removes all the event listeners that * `connectedCallback` added.

* `disconnectedCallback` cleans up the event handlers set up in * `connectedCallback`.

* `disconnectedCallback()` unregisters the event listeners that were set up * in `connectedCallback()`.

* `disconnectedCallback()` fires when the element is removed from the DOM. * It's a good place to do clean up work like releasing references and

* `disconnectedCallback()` removes the event listeners that * `connectedCallback` added.

* `disconnectedCallback()` fires when the element is removed from the DOM. * It's a good place to do clean up work like releasing references and

* If the `RadioGroup` is removed from the DOM, clean up any event * listeners.

* A getter for the first `HowtoRadioButton` child.

* A getter for the last `HowtoRadioButton` child.

* Properties and their corresponding attributes should mirror one another. * The property setter for `pressed` handles truthy/falsy values and