Under consideration

prop-for-that ships deliberately lean, but we considered a lot more, scrubbed from prior art (State.js, Obs.js) and extrapolated across the HTML elements. This page is the whole spectrum, from shipped to deferred to out of scope, so you can see what was weighed, and vote for what ships next.

→ Vote on the proposals board · + Propose something new

The spectrum

shipped ✅ → building 🔨 → proposed 🗳️ → platform may cover 🌐 → out of scope 🚫

✅ Shipped: in the package today.
🔨 v1: accepted, on the build list.
🗳️ Proposed: considered, not yet committed. Your votes decide.
🌐 Platform may cover: emerging CSS (scroll-state queries, :fullscreen, orientation MQ) may make these redundant; still vote if you need them now.
🚫 Out of scope: CSS or the platform already does it well.

🔨 Landing in v1

Beyond what’s already shipped, these are accepted for the first release.

Globals: modifiers (shift/ctrl/alt/meta), caps-lock, key-active, pointer-idle, memory, touch-points, document-size, ~~page-visible~~ ✅ shipped, ~~page-focused~~ ✅ shipped, idle, selection, location, uptime, gamepad, clock angles, fps extend, battery extend.
Element: viewport-pos, rect, dist-from-pointer, truncated, children, text-metrics.
Per-element: ~~color-input~~ ✅ shipped, ~~select~~ ✅ shipped, date-input, file-input, textarea, ~~form (completion %)~~ ✅ shipped as the form-state plugin, meter-progress, table, audio-analyser.
Stances: a capability plugin with delivery-mode, device-capability, connection-capability, conserve (built for @container style()).

🗳️ Proposed: vote to prioritize

Considered and viable, but not yet committed. Click a name to vote.

Global

Proposal	What it would expose
`pointer` extend	`pointer-down`, `buttons`, `type`, `pressure`, `tilt` (drawing UIs)
`pointer-velocity`	pointer `speed` + `angle` (momentum/inertia)
`screen`	screen size, avail size, colour depth (const)
`screen-orientation`	physical device `angle` + portrait flag
`network` extend	`downlink-max`
`motion` extend	rotation rate, acceleration incl. gravity
`geo` extend	`altitude`, `heading`, `speed`
`light`	ambient light `lux` (rare support)
`gyroscope` / `magnetometer` / `gravity`	Generic Sensor API
`js-memory`	heap used / heap % (Chromium-only)
`date`	calendar parts: `weekday`, `day`, `month`, `year`, `day-of-year`, `days-in-month`, `is-weekend`, `is-am` (the calendar companion to `clock`’s time-of-day)
`input-modality`	whether the last input was keyboard / mouse / touch / pen — adaptive density, hit-targets, and focus rings beyond what `:focus-visible` scopes
`interacted`	`--const-interacted` latches on the first user gesture — “tap to start” overlays, autoplay/audio unlock, deferring heavy work until engagement
`drag-state`	a drag op is in progress (global `dragging`); per-element `drag-over` (valid drop target) and `dragging-self` — no CSS pseudo exists for these
`intl`	FOUC-safe i18n consts: timezone offset, first weekday, 12/24-hour, `lang` (so a `date`-driven calendar starts the week correctly)
`storage`	quota usage % + persisted flag (`navigator.storage.estimate`) — “almost full” warnings, gating offline features
`permissions`	granted / denied / prompt per permission (notifications, camera, mic, geo) — show an “enable” nudge only while the state is prompt
`responsiveness`	main-thread-busy from PerformanceObserver `longtask` — back off effects when janky (distinct from `fps` cadence and `cpu-pressure` tier)
`modifier-locks` extend	`num-lock`, `scroll-lock` alongside the v1 `caps-lock` (one `getModifierState` call)
~~`navigation`~~ ✅ shipped as the `nav-type` plugin	`--const-nav-type` (`navigate` / `reload` / `back_forward` / `prerender`, from `performance.getEntriesByType('navigation')[0].type`) — branch styling on how the user arrived. Rides the writer (lands post-paint); read the same value in a `<head>` script for a pre-paint constant
`page-lifecycle`	the suspension layer beneath `page-visible`: `--const-bfcache-restored` (latches when the page was restored from the back/forward cache, via `pageshow.persisted`) and `--live-frozen` (Page Lifecycle `freeze`/`resume`)
`user-activation`	`--live-user-active` from `navigator.userActivation.isActive` (transient activation) — the live “interacting right now” complement to the sticky `interacted` latch, for gating autoplay / audio-unlock windows

Why not pageswap / pagereveal? Those cross-document View Transition hooks fire before the first rendering opportunity and exist to configure or skip a transition imperatively — the opposite of this library’s read-state-then-rAF-flush model, which writes after paint. The one durable thing worth reading at that moment, how the user arrived, is surfaced synchronously instead via the navigation const above.

Element & per-element

Proposal	What it would expose
`size` extend	content box, inline/block size
`visibility` extend	`in-viewport`, `time-visible`, `fully-visible`
`field` extend	~~`remaining`, `fill-pct`, granular validity flags~~ ✅ shipped in the `field` plugin; `focused` still proposed (and the `field-state` plugin ships the interaction states: `dirty`/`pristine`, `touched`/`untouched`, `changed`, `submitted`)
`media` extend	buffered, played, muted, rate, ended, seeking, video dims, PiP
`canvas`	canvas width / height
`link`	`external`, `current` (nav highlighting)
`caret`	caret position, selection range
`field-state` extend	`[contenteditable]` support — dirty / changed / touched for rich-text editors, which CSS can’t see
`img-color` extend	palette beyond the dominant colour: secondary/accent swatches, average vs. dominant (the `img-color` plugin ships the dominant colour today)

🌐 The platform may cover these

Emerging CSS may make these redundant; they’re listed for transparency. Vote if you need them before browser support lands.

Proposal	Native alternative
`scroll-state` (`scrolled`, `at-top`, `at-bottom`)	`scroll-state()` container queries
`overflow` (is-overflowing)	`scroll-state()` queries
`scrollable`	`scroll-state()` queries
`stuck` (sticky-stuck)	`scroll-state(stuck)`
`fullscreen`	`:fullscreen`
`orientation-layout` (`landscape`)	`orientation` media query
`details` (`open`)	`[open]` / `:modal`
`anim-state` (`animating`)	none yet

🚫 Out of scope

CSS or the platform already does these well, so prop-for-that won’t duplicate them:

Interaction states: :hover, :focus, :focus-within, :focus-visible, :active, :checked, :disabled, :required, :placeholder-shown, :empty, :has(), [open], :modal, :fullscreen, :popover-open.
Preferences: prefers-color-scheme, prefers-reduced-motion, prefers-reduced-data, prefers-contrast, forced-colors, inverted-colors.
Layout queries: media / container / @container style() queries; orientation, resolution, aspect-ratio MQ.
Units: vw/vh/dvh/svh/lvh/vmin/vmax, cqw/cqh, env() safe-area insets.
Scroll-linked: scroll position/progress → animation-timeline: scroll() / view() (compositor-driven, no library needed).