[rjsgud49]

No linked issue; found while reading the source.

📝 Description

getFileMimeType looks up the file extension in mimeTypesMap as is, but the map keys are lowercase. Files with an uppercase extension get no mime type.

⛳️ Current behavior (updates)

getFileMimeType("photo.png") // "image/png"
getFileMimeType("IMG_0001.HEIC") // null
getFileMimeType("PHOTO.JPG") // null

isValidFileType uses getFileMimeType when file.type is empty (e.g. HEIC photos on Windows/Chrome, or files from some drag-and-drop sources). So with accept="image/*", IMG_0001.HEIC is rejected while img_0001.heic is accepted. Extension accepts like .png already ignore case, so only mime accepts are affected.

🚀 New behavior

• The extension is lowercased before the lookup, so IMG_0001.HEIC resolves to image/heic and passes accept="image/*".
• Added a patch changeset for @zag-js/file-utils.

💣 Is this a breaking change (Yes/No):

No

📝 Additional Information

• New get-file-mime-type.test.ts and one new case in is-valid-file-type.test.ts. Both fail on main and pass with the fix.
• vitest run packages/utilities packages/machines/file-upload: 808 passed, 1 skipped. tsc --noEmit and eslint src tests pass for the package, and tsup builds it.

[changeset-bot]

🦋 Changeset detected

Latest commit: 19005b6

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 85 packages

Name	Type
@zag-js/file-utils	Patch
@zag-js/file-upload	Patch
@zag-js/anatomy-icons	Patch
@zag-js/anatomy	Patch
@zag-js/core	Patch
@zag-js/docs	Patch
@zag-js/preact	Patch
@zag-js/react	Patch
@zag-js/solid	Patch
@zag-js/svelte	Patch
@zag-js/vanilla	Patch
@zag-js/vue	Patch
@zag-js/accordion	Patch
@zag-js/angle-slider	Patch
@zag-js/async-list	Patch
@zag-js/avatar	Patch
@zag-js/carousel	Patch
@zag-js/cascade-select	Patch
@zag-js/checkbox	Patch
@zag-js/clipboard	Patch
@zag-js/collapsible	Patch
@zag-js/color-picker	Patch
@zag-js/combobox	Patch
@zag-js/date-input	Patch
@zag-js/date-picker	Patch
@zag-js/dialog	Patch
@zag-js/drawer	Patch
@zag-js/editable	Patch
@zag-js/floating-panel	Patch
@zag-js/hover-card	Patch
@zag-js/image-cropper	Patch
@zag-js/listbox	Patch
@zag-js/marquee	Patch
@zag-js/menu	Patch
@zag-js/navigation-menu	Patch
@zag-js/number-input	Patch
@zag-js/pagination	Patch
@zag-js/password-input	Patch
@zag-js/pin-input	Patch
@zag-js/popover	Patch
@zag-js/presence	Patch
@zag-js/progress	Patch
@zag-js/qr-code	Patch
@zag-js/radio-group	Patch
@zag-js/rating-group	Patch
@zag-js/scroll-area	Patch
@zag-js/select	Patch
@zag-js/signature-pad	Patch
@zag-js/slider	Patch
@zag-js/splitter	Patch
@zag-js/steps	Patch
@zag-js/switch	Patch
@zag-js/tabs	Patch
@zag-js/tags-input	Patch
@zag-js/timer	Patch
@zag-js/toast	Patch
@zag-js/toc	Patch
@zag-js/toggle-group	Patch
@zag-js/toggle	Patch
@zag-js/tooltip	Patch
@zag-js/tour	Patch
@zag-js/tree-view	Patch
@zag-js/store	Patch
@zag-js/types	Patch
@zag-js/aria-hidden	Patch
@zag-js/auto-resize	Patch
@zag-js/collection	Patch
@zag-js/color-utils	Patch
@zag-js/utils	Patch
@zag-js/date-utils	Patch
@zag-js/dismissable	Patch
@zag-js/dom-query	Patch
@zag-js/focus-trap	Patch
@zag-js/focus-visible	Patch
@zag-js/highlight-word	Patch
@zag-js/hotkeys	Patch
@zag-js/i18n-utils	Patch
@zag-js/interact-outside	Patch
@zag-js/json-tree-utils	Patch
@zag-js/live-region	Patch
@zag-js/popper	Patch
@zag-js/rect-utils	Patch
@zag-js/remove-scroll	Patch
@zag-js/scroll-snap	Patch
@zag-js/stringify-state	Patch

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Project	Deployment	Actions	Updated
zag-nextjs	Ready	Preview	Oct 21, 2026 3:22pm UTC
zag-solid	Building	Preview	Oct 21, 2026 3:22pm UTC
zag-svelte	Ready	Preview	Oct 21, 2026 3:22pm UTC
zag-vue	Ready	Preview	Oct 21, 2026 3:22pm UTC

1 Skipped Deployment

Project	Deployment	Actions	Updated
zag-website	Ignored	Preview	Oct 21, 2026 3:22pm UTC