Case-insensitive CSS attribute selectors

Including an `i` before the `]` in a CSS attribute selector causes the attribute value to be matched in an ASCII-case-insensitive manner. For example, `[b="xyz" i]` would match both `<a b="xyz">` and `<a b="XYZ">`.

Element.insertAdjacentElement() & Element.insertAdjacentText()

Methods for inserting an element or text before or after a given element, or appending or prepending an element or text to a given element's list of children.

Element.insertAdjacentHTML()

Inserts a string of HTML into a specified position in the DOM relative to the given element.

Intrinsic & Extrinsic Sizing

Allows for the heights and widths to be specified in intrinsic values using the `max-content`, `min-content`, `fit-content` and `stretch` (formerly `fill`) properties.

Upgrade Insecure Requests

Declare that browsers should transparently upgrade HTTP resources on a website to HTTPS.

element api: insertadjacentelement

element api: insertadjacenthtml

element api: insertadjacenthtml: requires `trustedhtml` instance when trusted types are enforced

element api: insertadjacenttext

installevent api

installevent api: addroutes

node api: insertbefore

observable api: inspect

range api: insertnode

css property: inset

css property: inset-block

css property: inset-block-end

css property: inset-block-start

css property: inset-block: auto

css property: inset-inline

css property: inset-inline-end

css property: inset: `anchor()`

css property: inset: auto

html element: ins

html element: ins: cite

html element: ins: datetime

javascript built-in: temporal api: instant

javascript built-in: temporal api: instant: add

javascript built-in: temporal api: instant: compare

javascript built-in: temporal api: instant: epochmilliseconds

javascript built-in: temporal api: instant: epochnanoseconds

javascript built-in: temporal api: instant: equals

javascript built-in: temporal api: instant: from

javascript built-in: temporal api: instant: fromepochmilliseconds

javascript built-in: temporal api: instant: fromepochnanoseconds

javascript built-in: temporal api: instant: `instant()` constructor

javascript built-in: temporal api: instant: round

javascript built-in: temporal api: instant: since

javascript built-in: temporal api: instant: subtract

javascript built-in: temporal api: instant: tojson

javascript built-in: temporal api: instant: tolocalestring

javascript built-in: temporal api: instant: tostring

javascript built-in: temporal api: instant: tozoneddatetimeiso

javascript built-in: temporal api: instant: until

javascript built-in: temporal api: instant: valueof

javascript built-in: temporal api: now: instant