emoji-picker-element

<emoji-picker></emoji-picker>

A lightweight emoji picker, distributed as a web component.

Features:

• Supports Emoji v15.1 (depending on OS) and custom emoji
• Uses IndexedDB, so it consumes far less memory than other emoji pickers
• Small bundle size (~12.5kB min+gz)
• Renders native emoji by default, with support for custom fonts
• Accessible by default
• Framework and bundler not required, just add a <script> tag and use it

Table of contents:

• emoji-picker-element
  • Usage
    • Examples
    • Emoji support
      • Custom emoji font
      • Polyfilling flag emoji on Windows
  • Styling
    • Size
    • Dark mode
    • CSS variables
    • Focus outline
    • Small screen sizes
    • Custom styling
  • JavaScript API
    • Picker
      • Events
        • emoji-click
        • skin-tone-change
      • Internationalization
        • Built-in translations
      • Custom category order
    • Database
      • Constructors
        • constructor
      • Accessors
        • customEmoji
      • Methods
        • close
        • delete
        • getEmojiByGroup
        • getEmojiBySearchQuery
        • getEmojiByShortcode
        • getEmojiByUnicodeOrName
        • getPreferredSkinTone
        • getTopFavoriteEmoji
        • incrementFavoriteEmojiCount
        • ready
        • setPreferredSkinTone
    • Custom emoji
    • Tree-shaking
    • Within a meta-framework (Next.js, SvelteKit, etc.)
    • Within a Svelte project
  • Data and offline
    • Data source and JSON format
    • Shortcodes
    • Cache performance
    • emojibase-data compatibility (deprecated)
    • Trimming the emoji data (deprecated)
    • Offline-first
    • Environments without IndexedDB
  • Design decisions
    • IndexedDB
    • Native emoji
    • JSON loading
    • Browser support
  • Contributing

Usage

Via npm:

npm install emoji-picker-element

import 'emoji-picker-element';

Or as a <script> tag:

<script type="module" src="https://cdn.jsdelivr.net/npm/emoji-picker-element@^1/index.js"></script>

Then use the HTML:

<emoji-picker></emoji-picker>

And listen for emoji-click events:

document.querySelector('emoji-picker')
  .addEventListener('emoji-click', event => console.log(event.detail));

This will log:

{
  "emoji": {
    "annotation": "grinning face",
    "group": 0,
    "order": 1,
    "shortcodes": [ "grinning_face", "grinning" ],
    "tags": [ "face", "grin" ],
    "unicode": "😀",
    "version": 1,
    "emoticon": ":D"
  },
  "skinTone": 0,
  "unicode": "😀"
}

Examples

• Demo (source)
• Button with tooltip/popover (source)
• Inserting emoji into a text input (source)
• In a React app (source)
• Custom emoji font (source)
• Fallback for missing flag emoji on Windows (source)

Emoji support

Emoji support varies across browsers and operating systems. By default, emoji-picker-element will hide unsupported emoji from the picker.

To work around this, you can use a custom emoji font or polyfill flag emoji on Windows.

Custom emoji font

To use a custom emoji font, first set the --emoji-font-family CSS property:

emoji-picker {
  --emoji-font-family: MyCustomFont;
}

Then, specify the maximum emoji version supported by the font. (See Emojipedia for a list of versions.)

In HTML:

<emoji-picker emoji-version="15.0"></emoji-picker>

Or JavaScript:

const picker = new Picker({
  emojiVersion: 15.0
});

If the emoji-version/emojiVersion option is set, then emoji-picker-element will not attempt to detect unsupported emoji or hide them.

Also note that support for color fonts varies across browsers and OSes, and some browsers may have bugs or not render the font at all. Be careful to test your supported browsers when using this approach.

Polyfilling flag emoji on Windows

As of this writing, Windows does not support country flag emoji. This is only a problem in Chromium-based browsers, because Firefox ships with its own emoji font.

To work around this, you can use country-flag-emoji-polyfill:

import { polyfillCountryFlagEmojis } from 'country-flag-emoji-polyfill';

// emoji-picker-element will use "Twemoji Mozilla" and fall back to other fonts for non-flag emoji
polyfillCountryFlagEmojis('Twemoji Mozilla');

Note that you do not need to do this if you are using a custom emoji font.

Styling

emoji-picker-element uses Shadow DOM, so its inner styling cannot be (easily) changed with arbitrary CSS. Refer to the API below for style customization.

Size

emoji-picker-element has a default size, but you can change it to whatever you want:

emoji-picker {
  width: 400px;
  height: 300px;
}

For instance, to make it expand to fit whatever container you give it:

emoji-picker {
  width: 100%;
  height: 100%;
}

Dark mode

By default, emoji-picker-element will automatically switch to dark mode based on prefers-color-scheme. Or you can add the class dark or light to force dark/light mode:

<emoji-picker class="dark"></emoji-picker>
<emoji-picker class="light"></emoji-picker>

CSS variables

Most colors and sizes can be styled with CSS variables. For example:

emoji-picker {
  --num-columns: 6;
  --emoji-size: 3rem;
  --background: gray;
}

Here is a full list of options:

| Variable | Default | Default (dark) | Description | | ---------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------- | -------------- | ---------------------------------------------------------------------------------------------------- | | --background | #fff | #222 | Background of the entire <emoji-picker> | | --border-color | #e0e0e0 | #444 | | | --border-radius | 0 | | Border radius of the entire picker | | --border-size | 1px | | Width of border used in most of the picker | | --button-active-background | #e6e6e6 | #555555 | Background of an active button | | --button-hover-background | #d9d9d9 | #484848 | Background of a hovered button | | --category-emoji-padding | var(--emoji-padding) | | Vertical/horizontal padding on category emoji, if you want it to be different from --emoji-padding | | --category-emoji-size | var(--emoji-size) | | Width/height of category emoji, if you want it to be different from --emoji-size | | --category-font-color | #111 | #efefef | Font color of custom emoji category headings | | --category-font-size | 1rem | | Font size of custom emoji category headings | | --emoji-font-family | "Twemoji Mozilla","Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol","Noto Color Emoji","EmojiOne Color","Android Emoji",sans-serif | | Font family for a custom emoji font (as opposed to native emoji) | | --emoji-padding | 0.5rem | | Vertical and horizontal padding on emoji | | --emoji-size | 1.375rem | | Width and height of all emoji | | --indicator-color | #385ac1 | #5373ec | Color of the nav indicator | | --indicator-height | 3px | | Height of the nav indicator | | --input-border-color | #999 | #ccc | | | --input-border-radius | 0.5rem | | | | --input-border-size | 1px | | | | --input-font-color | #111 | #efefef | | | --input-font-size | 1rem | | | | --input-line-height | 1.5 | | | | --input-padding | 0.25rem | | | | --input-placeholder-color | #999 | #ccc | | | --num-columns | 8 | | How many columns to display in the emoji grid | | --outline-color | #999 | #fff | Focus outline color | | --outline-size | 2px | | Focus outline width | | --skintone-border-radius | 1rem | | Border radius of the skintone dropdown |

Focus outline

For accessibility reasons, emoji-picker-element displays a prominent focus ring for keyboard users. This uses :focus-visible under the hood. To properly support browsers that do not support :focus-visible, you can use the focus-visible polyfill, e.g.:

import 'focus-visible';

const picker = new Picker();
applyFocusVisiblePolyfill(picker.shadowRoot);

emoji-picker-element already ships with the proper CSS for both the :focus-visible standard and the polyfill.

Small screen sizes

For small screen sizes, you should probably add some CSS like the following:

@media screen and (max-width: 320px) {
  emoji-picker {
    --num-columns: 6;
    --category-emoji-size: 1.125rem;
  }
}

emoji-picker-element does not ship with any CSS to explicitly handle small screen sizes. The right CSS depends on which screen sizes your app supports, and the size of the picker within your app. Perhaps in the future container queries can solve this problem.

Custom styling

If you absolutely must go beyond the styling API above, you can do something like this:

const style = document.createElement('style');
style.textContent = `/* custom shadow dom styles here */`
picker.shadowRoot.appendChild(style);

JavaScript API

Picker

Basic usage:

import { Picker } from 'emoji-picker-element';
const picker = new Picker();
document.body.appendChild(picker);

The new Picker(options) constructor supports several options:

| Name | Type | Default | Description | |-------------------------|---------------|------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------| | customCategorySorting | function | - | Function to sort custom category strings (sorted alphabetically by default) | | customEmoji | CustomEmoji[] | - | Array of custom emoji | | dataSource | string | "https://cdn.jsdelivr.net/npm/emoji-picker-element-data@^1/en/emojibase/data.json" | URL to fetch the emoji data from (data-source when used as an attribute) | | emojiVersion | number | - | Maximum supported emoji version as a number (e.g. 14.0 or 13.1). Setting this disables the default emoji support detection. | | i18n | I18n | - | i18n object (see below for details) | | locale | string | "en" | Locale string | | skinToneEmoji | string | "🖐️" | The emoji to use for the skin tone picker (skin-tone-emoji when used as an attribute) |

For instance:

const picker = new Picker({
  locale: 'fr',
  dataSource: '/fr-emoji.json'
})

These values can also be set at runtime:

const picker = new Picker();
picker.dataSource = '/my-emoji.json';

Some values can also be set as declarative attributes:

<emoji-picker
  locale="fr"
  data-source="/fr-emoji.json"
  skin-tone-emoji="✌"
></emoji-picker>

Note that complex properties like i18n or customEmoji are not supported as attributes, because the DOM only supports string attributes, not complex objects.

Events

emoji-click

The emoji-click event is fired when an emoji is selected by the user. Example format:

{
  emoji: {
    annotation: 'thumbs up',
    group: 1,
    order: 280,
    shortcodes: ['thumbsup', '+1', 'yes'],
    tags: ['+1', 'hand', 'thumb', 'up'],
    unicode: '👍️',
    version: 0.6,
    skins: [
      { tone: 1, unicode: '👍🏻', version: 1 },
      { tone: 2, unicode: '👍🏼', version: 1 },
      { tone: 3, unicode: '👍🏽', version: 1 },
      { tone: 4, unicode: '👍🏾', version: 1 },
      { tone: 5, unicode: '👍🏿', version: 1 }
    ]
  },
  skinTone: 4,
  unicode: '👍🏾'
}

And usage:

picker.addEventListener('emoji-click', event => {
  console.log(event.detail); // will log something like the above
});

Note that unicode will represent whatever the emoji should look like with the given skinTone. If the skinTone is 0, or if the emoji has no skin tones, then no skin tone is applied to unicode.

skin-tone-change

This event is fired whenever the user selects a new skin tone. Example format:

{
  skinTone: 5
}

And usage:

picker.addEventListener('skin-tone-change', event => {
  console.log(event.detail); // will log something like the above
})

Note that skin tones are an integer from 0 (default) to 1 (light) through 5 (dark).

Internationalization

The i18n parameter specifies translations for the picker interface. Here is the default English i18n object:

{
  "categories": {
    "custom": "Custom",
    "smileys-emotion": "Smileys and emoticons",
    "people-body": "People and body",
    "animals-nature": "Animals and nature",
    "food-drink": "Food and drink",
    "travel-places": "Travel and places",
    "activities": "Activities",
    "objects": "Objects",
    "symbols": "Symbols",
    "flags": "Flags"
  },
  "categoriesLabel": "Categories",
  "emojiUnsupportedMessage": "Your browser does not support color emoji.",
  "favoritesLabel": "Favorites",
  "loadingMessage": "Loading…",
  "networkErrorMessage": "Could not load emoji.",
  "regionLabel": "Emoji picker",
  "searchDescription": "When search results are available, press up or down to select and enter to choose.",
  "searchLabel": "Search",
  "searchResultsLabel": "Search results",
  "skinToneDescription": "When expanded, press up or down to select and enter to choose.",
  "skinToneLabel": "Choose a skin tone (currently {skinTone})",
  "skinTones": [
    "Default",
    "Light",
    "Medium-Light",
    "Medium",
    "Medium-Dark",
    "Dark"
  ],
  "skinTonesLabel": "Skin tones"
}

Note that some of these strings are only visible to users of screen readers. They are still important for accessibility!

Built-in translations

Community-provided translations for some languages are available. You can use them like so:

import fr from 'emoji-picker-element/i18n/fr';
import de from 'emoji-picker-element/i18n/de';

// French
picker.i18n = fr;

// German
picker.i18n = de;

Note that translations for the interface (i18n) are not the same as translations for the emoji data (dataSource and locale). To support both, you should do something like:

import fr from 'emoji-picker-element/i18n/fr';

const picker = new Picker({ 
  i18n: fr,
  locale: 'fr',
  dataSource: 'https://cdn.jsdelivr.net/npm/emoji-picker-element-data@^1/fr/emojibase/data.json',
});

If a built-in translation for your target language is not available, you can also write your own translation and pass it in as i18n. Please feel free to contribute your translation here.

Custom category order

By default, custom categories are sorted alphabetically. To change this, pass in your own customCategorySorting:

picker.customCategorySorting = (category1, category2) => { /* your sorting code */ };

This function should accept two strings and return a number.

Custom emoji with no category will pass in undefined. By default, these are shown first, with the label "Custom" (determined by i18n.categories.custom).

Database

You can work with the database API separately, which allows you to query emoji the same way that the picker does:

import { Database } from 'emoji-picker-element';

const database = new Database();
await database.getEmojiBySearchPrefix('elephant'); // [{unicode: "🐘", ...}]

Note that under the hood, IndexedDB data is partitioned based on the locale. So if you create two Databases with two different locales, it will store twice as much data.

Also note that, unlike the picker, the database does not filter emoji based on whether they are supported by the current browser/OS or not. To detect emoji support, you can use a library like is-emoji-supported.

Full API:

Constructors

constructor

+ new Database(__namedParameters: object): Database

Create a new Database.

Note that multiple Databases pointing to the same locale will share the same underlying IndexedDB connection and database.

Parameters:

▪Default value __namedParameters: object= {}

Name | Type | Default | Description | ------ | ------ | ------ | ------ | customEmoji | CustomEmoji[] | [] | Array of custom emoji | dataSource | string | "https://cdn.jsdelivr.net/npm/emoji-picker-element-data@^1/en/emojibase/data.json" | URL to fetch the emoji data from | locale | string | "en" | Locale string |

Returns: Database

Accessors

customEmoji

• get customEmoji(): CustomEmoji[]

Return the custom emoji associated with this Database, or the empty array if none.

Returns: CustomEmoji[]

• set customEmoji(customEmoji: CustomEmoji[]): void

Set the custom emoji for this database. Throws an error if custom emoji are not in the correct format.

Parameters:

Name | Type | Description | ------ | ------ | ------ | customEmoji | CustomEmoji[] | |

Returns: void

Methods

close

▸ close(): Promise‹void›

Closes the underlying IndexedDB connection. The Database is not usable after that (or any other Databases with the same locale).

Note that as soon as any other non-close/delete method is called, the database will automatically reopen.

Returns: Promise‹void›

delete

▸ delete(): Promise‹void›

Deletes the underlying IndexedDB database. The Database is not usable after that (or any other Databases with the same locale).

Note that as soon as any other non-close/delete method is called, the database will be recreated.

Returns: Promise‹void›

getEmojiByGroup

▸ getEmojiByGroup(group: number): Promise‹NativeEmoji[]›

Returns all emoji belonging to a group, ordered by order. Only returns native emoji; custom emoji don't belong to a group.

Non-numbers throw an error.

Parameters:

Name | Type | Description | ------ | ------ | ------ | group | number | the group number |

Returns: Promise‹NativeEmoji[]›

getEmojiBySearchQuery

▸ getEmojiBySearchQuery(query: string): Promise‹Emoji[]›

Returns all emoji matching the given search query, ordered by order.

Empty/null strings throw an error.

Parameters:

Name | Type | Description | ------ | ------ | ------ | query | string | search query string |

Returns: Promise‹Emoji[]›

getEmojiByShortcode

▸ getEmojiByShortcode(shortcode: string): Promise‹Emoji | null›

Return a single emoji matching the shortcode, or null if not found.

The colons around the shortcode should not be included when querying, e.g. use "slight_smile", not ":slight_smile:". Uppercase versus lowercase does not matter. Empty/null strings throw an error.

Parameters:

Name | Type | Description | ------ | ------ | ------ | shortcode | string | |

Returns: Promise‹Emoji | null›

getEmojiByUnicodeOrName

▸ getEmojiByUnicodeOrName(unicodeOrName: string): Promise‹Emoji | null›

Return a single native emoji matching the unicode string, or a custom emoji matching the name, or null if not found.

In the case of native emoji, the unicode string can be either the main unicode string, or the unicode of one of the skin tone variants.

Empty/null strings throw an error.

Parameters:

Name | Type | Description | ------ | ------ | ------ | unicodeOrName | string | unicode (native emoji) or name (custom emoji) |

Returns: Promise‹Emoji | null›

getPreferredSkinTone

▸ getPreferredSkinTone(): Promise‹SkinTone›

Get the user's preferred skin tone. Returns 0 if not found.

Returns: Promise‹SkinTone›

getTopFavoriteEmoji

▸ getTopFavoriteEmoji(limit: number): Promise‹Emoji[]›

Get the top favorite emoji in descending order. If there are no favorite emoji yet, returns an empty array.

Parameters:

Name | Type | Description | ------ | ------ | ------ | limit | number | maximum number of results to return |

Returns: Promise‹Emoji[]›

incrementFavoriteEmojiCount

▸ incrementFavoriteEmojiCount(unicodeOrName: string): Promise‹void›

Increment the favorite count for an emoji by one. The unicode string must be non-empty. It should correspond to the base (non-skin-tone) unicode string from the emoji object, or in the case of custom emoji, it should be the name.

Parameters:

Name | Type | Description | ------ | ------ | ------ | unicodeOrName | string | unicode of a native emoji, or name of a custom emoji |

Returns: Promise‹void›

ready

▸ ready(): Promise‹void›

Resolves when the Database is ready, or throws an error if the Database could not initialize.

Note that you don't need to do this before calling other APIs – they will all wait for this promise to resolve before doing anything.

Returns: Promise‹void›

setPreferredSkinTone

▸ setPreferredSkinTone(skinTone: SkinTone): Promise‹void›

Set the user's preferred skin tone. Non-numbers throw an error.

Parameters:

Name | Type | Description | ------ | ------ | ------ | skinTone | SkinTone | preferred skin tone |

Returns: Promise‹void›

Custom emoji

Both the Picker and the Database support custom emoji. Unlike regular emoji, custom emoji are kept in-memory. (It's assumed that they're small, and they might frequently change, so there's not much point in storing them in IndexedDB.)

Custom emoji should follow the format:

[
  {
    name: 'Garfield',
    shortcodes: ['garfield'],
    url: 'http://example.com/garfield.png',
    category: 'Cats'
  },
  {
    name: 'Heathcliff',
    shortcodes: ['heathcliff'],
    url: 'http://example.com/heathcliff.png',
    category: 'Cats'
  },
  {
    name: 'Scooby-Doo',
    shortcodes: ['scooby'],
    url: 'http://example.com/scooby.png',
    category: 'Dogs'
  }  
]

Note that names are assumed to be unique (case-insensitive), and it's assumed that the shortcodes have at least one entry.

The category is optional. If you don't provide it, then the custom emoji will appear in a single category called "Custom".

To pass custom emoji into the Picker:

const picker = new Picker({
  customEmoji: [ /* ... */ ]
});

Or the Database:

const database = new Database({
  customEmoji: [ /* ... */ ]
});

Custom emoji can also be set at runtime:

picker.customEmoji = [ /* ... */ ];
database.customEmoji = [ /* ... */ ];

Tree-shaking

If you want to import the Database without the Picker, or you want to code-split them separately, then do:

import Picker from 'emoji-picker-element/picker';
import Database from 'emoji-picker-element/database';

The reason for this is that Picker automatically registers itself as a custom element, following web component best practices. But this adds side effects, so bundlers like Webpack and Rollup do not tree-shake as well, unless the modules are imported from completely separate files.

Within a meta-framework (Next.js, SvelteKit, etc.)

Some meta-frameworks will attempt to server-side render (SSR) any dependencies you import. However, emoji-picker-element only supports client-side rendering – it does not work on the server side. If you attempt to import it on the server side, you will see an error like requestAnimationFrame is not defined.

To load emoji-picker-element only on the client side, use your meta-framework's technique for client-side-only imports. For example, you can use dynamic import()s with next/dynamic in Next.js or onMount() in SvelteKit.

emoji-picker-element is not designed for SSR. In most apps, an emoji picker should be lazy-loaded upon user interaction (for example, when the user clicks a button).

Within a Svelte project

[!WARNING]
emoji-picker-element is no longer based on Svelte, so importing from emoji-picker-element/svelte is now deprecated.

Previously, emoji-picker-element was based on Svelte v3/v4, and you could do:

import Picker from 'emoji-picker-element/svelte';

The goal was to slightly reduce the bundle size by sharing common svelte imports.

This is still supported for backwards compatibility, but it is deprecated and just re-exports the Picker. Instead, do:

import Picker from 'emoji-picker-element/picker';

Data and offline

Data source and JSON format

If you'd like to host the emoji data (dataSource) yourself, you can do:

npm install emoji-picker-element-data@^1

Then host node_modules/emoji-picker-element-data/en/emojibase/data.json (or other JSON files) on your web server.

const picker = new Picker({
  dataSource: '/path/to/my/webserver/data.json'
});

See emoji-picker-element-data for details.

Shortcodes

There is no standard for shortcodes, so unlike other emoji data, there is some disagreement as to what a "shortcode" actually is.

emoji-picker-element-data is based on emojibase-data, which offers several shortcode packs per language. For instance, you may choose shortcodes from GitHub, Slack, Discord, or Emojibase (the default). You can browse the available data files on jsdelivr and see more details on shortcodes in the Emojibase docs.

Cache performance

For optimal cache performance, it's recommended that your server expose an ETag header. If so, emoji-picker-element can avoid re-downloading the entire JSON file over and over again. Instead, it will do a HEAD request and just check the ETag.

If the server hosting the JSON file is not the same as the one containing the emoji picker, then the cross-origin server will also need to expose Access-Control-Allow-Origin: * and Access-Control-Allow-Headers: ETag (or Access-Control-Allow-Headers: * ). jsdelivr already does this, which is partly why it is the default.

Note that Safari does not currently support Access-Control-Allow-Headers: *, but it does support Access-Control-Allow-Headers: ETag.

If emoji-picker-element cannot use the ETag for any reason, it will fall back to the less performant option, doing a full GET request on every page load.

emojibase-data compatibility (deprecated)

Deprecated: in v1.3.0, emoji-picker-element switched from emojibase-data to emoji-picker-element-data as its default data source. You can still use emojibase-data, but only v5 is supported, not v6. Support may be removed in a later release.

When using emojibase-data, you must use the full emojibase-data JSON file, not the "compact" one (i.e. data.json, not compact.json).

Trimming the emoji data (deprecated)

Deprecated: in v1.3.0, emoji-picker-element switched from emojibase-data to emoji-picker-element-data as its default data source. With the new emoji-picker-element-data, there is no need to trim the emoji down to size. This function is deprecated and may be removed eventually.

If you are hosting the emojibase-data JSON file yourself and would like it to be as small as possible, then you can use the utility trimEmojiData function:

import trimEmojiData from 'emoji-picker-element/trimEmojiData.js';
import emojiBaseData from 'emojibase-data/en/data.json';

const trimmedData = trimEmojiData(emojiBaseData);

Or if your version of Node doesn't support ES modules:

const trimEmojiData = require('emoji-picker-element/trimEmojiData.cjs');

Offline-first

emoji-picker-element uses a "stale while revalidate" strategy to update emoji data. In other words, it will use any existing data it finds in IndexedDB, and lazily update via the dataSource in case that data has changed. This means it will work offline-first the second time it runs.

If you would like to manage the database yourself (e.g. to ensure that it's correctly populated before displaying the Picker), then create a new Database instance and wait for its ready() promise to resolve:

const database = new Database();
try {
  await database.ready();
} catch (err) {
  // Deal with any errors (e.g. offline)
}

If emoji-picker-element fails to fetch the JSON data the first time it loads, then it will display an error message.

Environments without IndexedDB

emoji-picker-element has a hard requirement on IndexedDB, and will not work without it.

For browsers that don't support IndexedDB, such as Firefox in private browsing mode, you can polyfill it using fake-indexeddb. Here is a working example and more details.

For Node.js environments such as Jest or JSDom, you can also use fake-indexeddb. A working example can be found in the tests for this very project.

Design decisions

Some of the reasoning behind why emoji-picker-element is built the way it is.

IndexedDB

The emojibase-data English JSON file is 854kB, and the "compact" version is still 543kB. That's a lot of data to keep in memory just for an emoji picker. And it's not as if that number is ever going down; the Unicode Consortium keeps adding more emoji every year.

Using IndexedDB has a few advantages:

1. We don't need to keep the full emoji data in memory at all times.
2. After the first load, there is no need to download, parse, and index the JSON file again, because it's already available in IndexedDB.
3. If you want, you can even load the IndexedDB data in a web worker, keeping the main thread free from non-UI data processing.

Native emoji

To avoid downloading a large sprite sheet or font file – which may look out-of-place on different platforms, or may have IP issues – emoji-picker-element only renders native emoji by default. This means it is limited to the emoji font actually installed on the user's device.

To avoid rendering ugly unsupported or half-supported emoji, emoji-picker-element will automatically detect emoji support and only render the supported characters. (So no empty boxes or awkward double emoji.) If no color emoji are supported by the browser/OS, then an error message is displayed (e.g. older browsers, some odd Linux configurations).

That said, emoji-picker-element does support custom emoji fonts if you really want.

JSON loading

Browsers deal with JSON more efficiently when it's loaded via fetch() rather than embedded in JavaScript. It's faster for the browser to parse JSON than JavaScript, becuase the data is being parsed in the more tightly-constrained JSON format than the generic JavaScript format.

Plus, embedding the JSON directly would mean re-parsing the entire object on second load, which is something we want to avoid since the data is already in IndexedDB.

Browser support

emoji-picker-element only supports the latest versions of Chrome, Firefox, and Safari, as well as equivalent browsers (Edge, Opera, etc.). If you need support for older browsers, you will need polyfills for the following things (non-exhaustive list):

• Custom elements
• Shadow DOM
• ES2019+

That said, older browsers may not have a color emoji font installed at all, so emoji-picker-element will not work in those cases.

Contributing

See CONTRIBUTING.md.