Conceal fontawesome5

[Freed-Wu]

\usepackage{fontawesome5} provides fontawesome 5 symbol in LaTeX. Older \usepackage{fontawesome} provides fontawesome 4 symbol in LaTeX.

Because https://github.com/FortAwesome/Font-Awesome#documentation, only conceal fontawesome5 is OK.

Now that Font Awesome 6 has been released we are marking version 5 as Long Term Suport (LTS). Version 5 will get critical bug fixes only. Version 3 and 4 are now end-of-life and we don't plan on releasing any further versions of the 4.x or 3.x.

This is an example:

syn match texCmd '\\faFile\>\|\\faIcon\%\(\[\%\(regular\|solid\)]\|\){file}' conceal cchar=
syn match texCmd '\\faFile\*\|\\faIcon\*\%\(\[\%\(regular\|solid\)]\|\){file}\|\\faIcon\%\(\[\%\(regular\|solid\)]\|\){file-alt}' conceal cchar=

% work
\faFile
\faIcon{file}
\faIcon[regular]{file}
\faIcon[solid]{file}
\faFile*
\faIcon*{file}
\faIcon*[regular]{file}
\faIcon*[solid]{file}
% don't work
\faFil
\faFilea
\faIcon{fil}
\faIcon[regula]{file}

This is a full list (1440 icons, achieved from fontawesome5 documentation),
their icons can be achieved from https://fontawesome.com/v5/cheatsheet/pro/solid:

" ~/.config/nvim/after/syntax/tex.vim
let s:fontawesome = {
      \ '500px': '',
      \ 'accessible-icon': '',
      \ 'accusoft': '',
      \ 'acquisitions-incorporated': '',
      \ 'adn': '',
      \ 'adversal': '',
      \ 'affiliatetheme': '',
      \ 'airbnb': '',
      \ 'algolia': '',
      \ 'alipay': '',
      \ 'amazon': '',
      \ 'amazon-pay': '',
      \ 'amilia': '',
      \ 'android': '',
      \ 'angellist': '',
      \ 'angrycreative': '',
      \ 'angular': '',
      \ 'app-store': '',
      \ 'app-store-ios': '',
      \ 'apper': '',
      \ 'apple': '',
      \ 'apple-pay': '',
      \ 'artstation': '',
      \ 'asymmetrik': '',
      \ 'atlassian': '',
      \ 'audible': '',
      \ 'autoprefixer': '',
      \ 'avianex': '',
      \ 'aviato': '',
      \ 'aws': '',
      \ 'bandcamp': '',
      \ 'battle-net': '',
      \ 'behance': '',
      \ 'behance-square': '',
      \ 'bimobject': '',
      \ 'bitbucket': '',
      \ 'bitcoin': '',
      \ 'bity': '',
      \ 'black-tie': '',
      \ 'blackberry': '',
      \ 'blogger': '',
      \ 'blogger-b': '',
      \ 'bluetooth': '',
      \ 'bluetooth-b': '',
      \ 'bootstrap': '',
      \ 'btc': '',
      \ 'buffer': '',
      \ 'buromobelexperte': '',
      \ 'buy-n-large': '',
      \ 'canadian-maple-leaf': '',
      \ 'cc-amazon-pay': '',
      \ 'cc-amex': '',
      \ 'cc-apple-pay': '',
      \ 'cc-diners-club': '',
      \ 'cc-discover': '',
      \ 'cc-jcb': '',
      \ 'cc-mastercard': '',
      \ 'cc-paypal': '',
      \ 'cc-stripe': '',
      \ 'cc-visa': '',
      \ 'centercode': '',
      \ 'centos': '',
      \ 'chrome': '',
      \ 'chromecast': '',
      \ 'cloudflare': '',
      \ 'cloudscale': '',
      \ 'cloudsmith': '',
      \ 'cloudversify': '',
      \ 'codepen': '',
      \ 'codiepie': '',
      \ 'confluence': '',
      \ 'connectdevelop': '',
      \ 'contao': '',
      \ 'cotton-bureau': '',
      \ 'cpanel': '',
      \ 'creative-commons': '',
      \ 'creative-commons-by': '',
      \ 'creative-commons-nc': '',
      \ 'creative-commons-nc-eu': '',
      \ 'creative-commons-nc-jp': '',
      \ 'creative-commons-nd': '',
      \ 'creative-commons-pd': '',
      \ 'creative-commons-pd-alt': '',
      \ 'creative-commons-remix': '',
      \ 'creative-commons-sa': '',
      \ 'creative-commons-sampling': '',
      \ 'creative-commons-sampling-plus': '',
      \ 'creative-commons-share': '',
      \ 'creative-commons-zero': '',
      \ 'critical-role': '',
      \ 'css3': '',
      \ 'css3-alt': '',
      \ 'cuttlefish': '',
      \ 'd-and-d': '',
      \ 'd-and-d-beyond': '',
      \ 'dailymotion': '',
      \ 'dashcube': '',
      \ 'deezer': '',
      \ 'delicious': '',
      \ 'deploydog': '',
      \ 'deskpro': '',
      \ 'dev': '',
      \ 'deviantart': '',
      \ 'dhl': '',
      \ 'diaspora': '',
      \ 'digg': '',
      \ 'digital-ocean': '',
      \ 'discord': '',
      \ 'discourse': '',
      \ 'dochub': '',
      \ 'docker': '',
      \ 'draft2digital': '',
      \ 'dribbble': '',
      \ 'dribbble-square': '',
      \ 'dropbox': '',
      \ 'drupal': '',
      \ 'dyalog': '',
      \ 'earlybirds': '',
      \ 'ebay': '',
      \ 'edge': '',
      \ 'edge-legacy': '',
      \ 'elementor': '',
      \ 'ello': '',
      \ 'ember': '',
      \ 'empire': '',
      \ 'envira': '',
      \ 'erlang': '',
      \ 'ethereum': '',
      \ 'etsy': '',
      \ 'evernote': '',
      \ 'expeditedssl': '',
      \ 'facebook': '',
      \ 'facebook-f': '',
      \ 'facebook-messenger': '',
      \ 'facebook-square': '',
      \ 'fantasy-flight-games': '',
      \ 'fedex': '',
      \ 'fedora': '',
      \ 'figma': '',
      \ 'firefox': '',
      \ 'firefox-browser': '',
      \ 'first-order': '',
      \ 'first-order-alt': '',
      \ 'firstdraft': '',
      \ 'flickr': '',
      \ 'flipboard': '',
      \ 'fly': '',
      \ 'font-awesome': '',
      \ 'font-awesome-alt': '',
      \ 'font-awesome-flag': '',
      \ 'fonticons': '',
      \ 'fonticons-fi': '',
      \ 'fort-awesome': '',
      \ 'fort-awesome-alt': '',
      \ 'forumbee': '',
      \ 'foursquare': '',
      \ 'free-code-camp': '',
      \ 'freebsd': '',
      \ 'fulcrum': '',
      \ 'galactic-republic': '',
      \ 'galactic-senate': '',
      \ 'get-pocket': '',
      \ 'gg': '',
      \ 'gg-circle': '',
      \ 'git': '',
      \ 'git-alt': '',
      \ 'git-square': '',
      \ 'github': '',
      \ 'github-alt': '',
      \ 'github-square': '',
      \ 'gitkraken': '',
      \ 'gitlab': '',
      \ 'gitter': '',
      \ 'glide': '',
      \ 'glide-g': '',
      \ 'gofore': '',
      \ 'goodreads': '',
      \ 'goodreads-g': '',
      \ 'google': '',
      \ 'google-drive': '',
      \ 'google-pay': '',
      \ 'google-play': '',
      \ 'google-plus': '',
      \ 'google-plus-g': '',
      \ 'google-plus-square': '',
      \ 'google-wallet': '',
      \ 'gratipay': '',
      \ 'grav': '',
      \ 'gripfire': '',
      \ 'grunt': '',
      \ 'guilded': '',
      \ 'gulp': '',
      \ 'hacker-news': '',
      \ 'hacker-news-square': '',
      \ 'hackerrank': '',
      \ 'hips': '',
      \ 'hire-a-helper': '',
      \ 'hive': '',
      \ 'hooli': '',
      \ 'hornbill': '',
      \ 'hotjar': '',
      \ 'houzz': '',
      \ 'html5': '',
      \ 'hubspot': '',
      \ 'ideal': '',
      \ 'imdb': '',
      \ 'innosoft': '',
      \ 'instagram': '',
      \ 'instagram-square': '',
      \ 'instalod': '',
      \ 'intercom': '',
      \ 'internet-explorer': '',
      \ 'invision': '',
      \ 'ioxhost': '',
      \ 'itch-io': '',
      \ 'itunes': '',
      \ 'itunes-note': '',
      \ 'java': '',
      \ 'jedi-order': '',
      \ 'jenkins': '',
      \ 'jira': '',
      \ 'joget': '',
      \ 'joomla': '',
      \ 'js': '',
      \ 'js-square': '',
      \ 'jsfiddle': '',
      \ 'kaggle': '',
      \ 'keybase': '',
      \ 'keycdn': '',
      \ 'kickstarter': '',
      \ 'kickstarter-k': '',
      \ 'korvue': '',
      \ 'laravel': '',
      \ 'lastfm': '',
      \ 'lastfm-square': '',
      \ 'leanpub': '',
      \ 'less': '',
      \ 'line': '',
      \ 'linkedin': '',
      \ 'linkedin-in': '',
      \ 'linode': '',
      \ 'linux': '',
      \ 'lyft': '',
      \ 'magento': '',
      \ 'mailchimp': '',
      \ 'mandalorian': '',
      \ 'markdown': '',
      \ 'mastodon': '',
      \ 'maxcdn': '',
      \ 'mdb': '',
      \ 'medapps': '',
      \ 'medium': '',
      \ 'medium-m': '',
      \ 'medrt': '',
      \ 'meetup': '',
      \ 'megaport': '',
      \ 'mendeley': '',
      \ 'microblog': '',
      \ 'microsoft': '',
      \ 'mix': '',
      \ 'mixcloud': '',
      \ 'mixer': '',
      \ 'mizuni': '',
      \ 'modx': '',
      \ 'monero': '',
      \ 'napster': '',
      \ 'neos': '',
      \ 'nimblr': '',
      \ 'node': '',
      \ 'node-js': '',
      \ 'npm': '',
      \ 'ns8': '',
      \ 'nutritionix': '',
      \ 'octopus-deploy': '',
      \ 'odnoklassniki': '',
      \ 'odnoklassniki-square': '',
      \ 'old-republic': '',
      \ 'opencart': '',
      \ 'openid': '',
      \ 'opera': '',
      \ 'optin-monster': '',
      \ 'orcid': '',
      \ 'osi': '',
      \ 'page4': '',
      \ 'pagelines': '',
      \ 'palfed': '',
      \ 'patreon': '',
      \ 'paypal': '',
      \ 'penny-arcade': '',
      \ 'perbyte': '',
      \ 'periscope': '',
      \ 'phabricator': '',
      \ 'phoenix-framework': '',
      \ 'phoenix-squadron': '',
      \ 'php': '',
      \ 'pied-piper': '',
      \ 'pied-piper-alt': '',
      \ 'pied-piper-hat': '',
      \ 'pied-piper-pp': '',
      \ 'pied-piper-square': '',
      \ 'pinterest': '',
      \ 'pinterest-p': '',
      \ 'pinterest-square': '',
      \ 'playstation': '',
      \ 'product-hunt': '',
      \ 'pushed': '',
      \ 'python': '',
      \ 'qq': '',
      \ 'quinscape': '',
      \ 'quora': '',
      \ 'r-project': '',
      \ 'raspberry-pi': '',
      \ 'ravelry': '',
      \ 'react': '',
      \ 'reacteurope': '',
      \ 'readme': '',
      \ 'rebel': '',
      \ 'red-river': '',
      \ 'reddit': '',
      \ 'reddit-alien': '',
      \ 'reddit-square': '',
      \ 'redhat': '',
      \ 'renren': '',
      \ 'replyd': '',
      \ 'researchgate': '',
      \ 'resolving': '',
      \ 'rev': '',
      \ 'rocketchat': '',
      \ 'rockrms': '',
      \ 'rust': '',
      \ 'safari': '',
      \ 'salesforce': '',
      \ 'sass': '',
      \ 'schlix': '',
      \ 'scribd': '',
      \ 'searchengin': '',
      \ 'sellcast': '',
      \ 'sellsy': '',
      \ 'servicestack': '',
      \ 'shirtsinbulk': '',
      \ 'shopify': '',
      \ 'shopware': '',
      \ 'simplybuilt': '',
      \ 'sistrix': '',
      \ 'sith': '',
      \ 'sketch': '',
      \ 'skyatlas': '',
      \ 'skype': '',
      \ 'slack': '',
      \ 'slack-hash': '',
      \ 'slideshare': '',
      \ 'snapchat': '',
      \ 'snapchat-ghost': '',
      \ 'snapchat-square': '',
      \ 'soundcloud': '',
      \ 'sourcetree': '',
      \ 'speakap': '',
      \ 'speaker-deck': '',
      \ 'spotify': '',
      \ 'squarespace': '',
      \ 'stack-exchange': '',
      \ 'stack-overflow': '',
      \ 'stackpath': '',
      \ 'staylinked': '',
      \ 'steam': '',
      \ 'steam-square': '',
      \ 'steam-symbol': '',
      \ 'sticker-mule': '',
      \ 'strava': '',
      \ 'stripe': '',
      \ 'stripe-s': '',
      \ 'studiovinari': '',
      \ 'stumbleupon': '',
      \ 'stumbleupon-circle': '',
      \ 'superpowers': '',
      \ 'supple': '',
      \ 'suse': '',
      \ 'swift': '',
      \ 'symfony': '',
      \ 'teamspeak': '',
      \ 'telegram': '',
      \ 'telegram-plane': '',
      \ 'tencent-weibo': '',
      \ 'the-red-yeti': '',
      \ 'themeco': '',
      \ 'themeisle': '',
      \ 'think-peaks': '',
      \ 'tiktok': '',
      \ 'trade-federation': '',
      \ 'trello': '',
      \ 'tumblr': '',
      \ 'tumblr-square': '',
      \ 'twitch': '',
      \ 'twitter': '',
      \ 'twitter-square': '',
      \ 'typo3': '',
      \ 'uber': '',
      \ 'ubuntu': '',
      \ 'uikit': '',
      \ 'umbraco': '',
      \ 'uncharted': '',
      \ 'uniregistry': '',
      \ 'unity': '',
      \ 'unsplash': '',
      \ 'untappd': '',
      \ 'ups': '',
      \ 'usb': '',
      \ 'usps': '',
      \ 'ussunnah': '',
      \ 'vaadin': '',
      \ 'viacoin': '',
      \ 'viadeo': '',
      \ 'viadeo-square': '',
      \ 'viber': '',
      \ 'vimeo': '',
      \ 'vimeo-square': '',
      \ 'vimeo-v': '',
      \ 'vine': '',
      \ 'vk': '',
      \ 'vnv': '',
      \ 'vuejs': '',
      \ 'watchman-monitoring': '',
      \ 'waze': '',
      \ 'weebly': '',
      \ 'weibo': '',
      \ 'weixin': '',
      \ 'whatsapp': '',
      \ 'whatsapp-square': '',
      \ 'whmcs': '',
      \ 'wikipedia-w': '',
      \ 'windows': '',
      \ 'wix': '',
      \ 'wizards-of-the-coast': '',
      \ 'wodu': '',
      \ 'wolf-pack-battalion': '',
      \ 'wordpress': '',
      \ 'wordpress-simple': '',
      \ 'wpbeginner': '',
      \ 'wpexplorer': '',
      \ 'wpforms': '',
      \ 'wpressr': '',
      \ 'xbox': '',
      \ 'xing': '',
      \ 'xing-square': '',
      \ 'y-combinator': '',
      \ 'yahoo': '',
      \ 'yammer': '',
      \ 'yandex': '',
      \ 'yandex-international': '',
      \ 'yarn': '',
      \ 'yelp': '',
      \ 'yoast': '',
      \ 'youtube': '',
      \ 'youtube-square': '',
      \ 'zhihu': '',
      \ 'ad': '',
      \ 'address-book': '',
      \ 'address-card': '',
      \ 'adjust': '',
      \ 'air-freshener': '',
      \ 'align-center': '',
      \ 'align-justify': '',
      \ 'align-left': '',
      \ 'align-right': '',
      \ 'allergies': '',
      \ 'ambulance': '',
      \ 'american-sign-language-interpreting': '',
      \ 'anchor': '',
      \ 'angle-double-down': '',
      \ 'angle-double-left': '',
      \ 'angle-double-right': '',
      \ 'angle-double-up': '',
      \ 'angle-down': '',
      \ 'angle-left': '',
      \ 'angle-right': '',
      \ 'angle-up': '',
      \ 'angry': '',
      \ 'ankh': '',
      \ 'apple-alt': '',
      \ 'archive': '',
      \ 'archway': '',
      \ 'arrow-alt-circle-down': '',
      \ 'arrow-alt-circle-left': '',
      \ 'arrow-alt-circle-right': '',
      \ 'arrow-alt-circle-up': '',
      \ 'arrow-circle-down': '',
      \ 'arrow-circle-left': '',
      \ 'arrow-circle-right': '',
      \ 'arrow-circle-up': '',
      \ 'arrow-down': '',
      \ 'arrow-left': '',
      \ 'arrow-right': '',
      \ 'arrow-up': '',
      \ 'arrows-alt': '',
      \ 'arrows-alt-h': '',
      \ 'arrows-alt-v': '',
      \ 'assistive-listening-systems': '',
      \ 'asterisk': '',
      \ 'at': '',
      \ 'atlas': '',
      \ 'atom': '',
      \ 'audio-description': '',
      \ 'award': '',
      \ 'baby': '',
      \ 'baby-carriage': '',
      \ 'backspace': '',
      \ 'backward': '',
      \ 'bacon': '',
      \ 'bacteria': '',
      \ 'bacterium': '',
      \ 'bahai': '',
      \ 'balance-scale': '',
      \ 'balance-scale-left': '',
      \ 'balance-scale-right': '',
      \ 'ban': '',
      \ 'band-aid': '',
      \ 'barcode': '',
      \ 'bars': '',
      \ 'baseball-ball': '',
      \ 'basketball-ball': '',
      \ 'bath': '',
      \ 'battery-empty': '',
      \ 'battery-full': '',
      \ 'battery-half': '',
      \ 'battery-quarter': '',
      \ 'battery-three-quarters': '',
      \ 'bed': '',
      \ 'beer': '',
      \ 'bell': '',
      \ 'bell-slash': '',
      \ 'bezier-curve': '',
      \ 'bible': '',
      \ 'bicycle': '',
      \ 'biking': '',
      \ 'binoculars': '',
      \ 'biohazard': '',
      \ 'birthday-cake': '',
      \ 'blender': '',
      \ 'blender-phone': '',
      \ 'blind': '',
      \ 'blog': '',
      \ 'bold': '',
      \ 'bolt': '',
      \ 'bomb': '',
      \ 'bone': '',
      \ 'bong': '',
      \ 'book': '',
      \ 'book-dead': '',
      \ 'book-medical': '',
      \ 'book-open': '',
      \ 'book-reader': '',
      \ 'bookmark': '',
      \ 'border-all': '',
      \ 'border-none': '',
      \ 'border-style': '',
      \ 'bowling-ball': '',
      \ 'box': '',
      \ 'box-open': '',
      \ 'box-tissue': '',
      \ 'boxes': '',
      \ 'braille': '',
      \ 'brain': '',
      \ 'bread-slice': '',
      \ 'briefcase': '',
      \ 'briefcase-medical': '',
      \ 'broadcast-tower': '',
      \ 'broom': '',
      \ 'brush': '',
      \ 'bug': '',
      \ 'building': '',
      \ 'bullhorn': '',
      \ 'bullseye': '',
      \ 'burn': '',
      \ 'bus': '',
      \ 'bus-alt': '',
      \ 'business-time': '',
      \ 'calculator': '',
      \ 'calendar': '',
      \ 'calendar-alt': '',
      \ 'calendar-check': '',
      \ 'calendar-day': '',
      \ 'calendar-minus': '',
      \ 'calendar-plus': '',
      \ 'calendar-times': '',
      \ 'calendar-week': '',
      \ 'camera': '',
      \ 'camera-retro': '',
      \ 'campground': '',
      \ 'candy-cane': '',
      \ 'cannabis': '',
      \ 'capsules': '',
      \ 'car': '',
      \ 'car-alt': '',
      \ 'car-battery': '',
      \ 'car-crash': '',
      \ 'car-side': '',
      \ 'caravan': '',
      \ 'caret-down': '',
      \ 'caret-left': '',
      \ 'caret-right': '',
      \ 'caret-square-down': '',
      \ 'caret-square-left': '',
      \ 'caret-square-right': '',
      \ 'caret-square-up': '',
      \ 'caret-up': '',
      \ 'carrot': '',
      \ 'cart-arrow-down': '',
      \ 'cart-plus': '',
      \ 'cash-register': '',
      \ 'cat': '',
      \ 'certificate': '',
      \ 'chair': '',
      \ 'chalkboard': '',
      \ 'chalkboard-teacher': '',
      \ 'charging-station': '',
      \ 'chart-area': '',
      \ 'chart-bar': '',
      \ 'chart-line': '',
      \ 'chart-pie': '',
      \ 'check': '',
      \ 'check-circle': '',
      \ 'check-double': '',
      \ 'check-square': '',
      \ 'cheese': '',
      \ 'chess': '',
      \ 'chess-bishop': '',
      \ 'chess-board': '',
      \ 'chess-king': '',
      \ 'chess-knight': '',
      \ 'chess-pawn': '',
      \ 'chess-queen': '',
      \ 'chess-rook': '',
      \ 'chevron-circle-down': '',
      \ 'chevron-circle-left': '',
      \ 'chevron-circle-right': '',
      \ 'chevron-circle-up': '',
      \ 'chevron-down': '',
      \ 'chevron-left': '',
      \ 'chevron-right': '',
      \ 'chevron-up': '',
      \ 'child': '',
      \ 'church': '',
      \ 'circle': '',
      \ 'circle-notch': '',
      \ 'city': '',
      \ 'clinic-medical': '',
      \ 'clipboard': '',
      \ 'clipboard-check': '',
      \ 'clipboard-list': '',
      \ 'clock': '',
      \ 'clone': '',
      \ 'closed-captioning': '',
      \ 'cloud': '',
      \ 'cloud-download-alt': '',
      \ 'cloud-meatball': '',
      \ 'cloud-moon': '',
      \ 'cloud-moon-rain': '',
      \ 'cloud-rain': '',
      \ 'cloud-showers-heavy': '',
      \ 'cloud-sun': '',
      \ 'cloud-sun-rain': '',
      \ 'cloud-upload-alt': '',
      \ 'cocktail': '',
      \ 'code': '',
      \ 'code-branch': '',
      \ 'coffee': '',
      \ 'cog': '',
      \ 'cogs': '',
      \ 'coins': '',
      \ 'columns': '',
      \ 'comment': '',
      \ 'comment-alt': '',
      \ 'comment-dollar': '',
      \ 'comment-dots': '',
      \ 'comment-medical': '',
      \ 'comment-slash': '',
      \ 'comments': '',
      \ 'comments-dollar': '',
      \ 'compact-disc': '',
      \ 'compass': '',
      \ 'compress': '',
      \ 'compress-alt': '',
      \ 'compress-arrows-alt': '',
      \ 'concierge-bell': '',
      \ 'cookie': '',
      \ 'cookie-bite': '',
      \ 'copy': '',
      \ 'copyright': '',
      \ 'couch': '',
      \ 'credit-card': '',
      \ 'crop': '',
      \ 'crop-alt': '',
      \ 'cross': '',
      \ 'crosshairs': '',
      \ 'crow': '',
      \ 'crown': '',
      \ 'crutch': '',
      \ 'cube': '',
      \ 'cubes': '',
      \ 'cut': '',
      \ 'database': '',
      \ 'deaf': '',
      \ 'democrat': '',
      \ 'desktop': '',
      \ 'dharmachakra': '',
      \ 'diagnoses': '',
      \ 'dice': '',
      \ 'dice-d20': '',
      \ 'dice-d6': '',
      \ 'dice-five': '',
      \ 'dice-four': '',
      \ 'dice-one': '',
      \ 'dice-six': '',
      \ 'dice-three': '',
      \ 'dice-two': '',
      \ 'digital-tachograph': '',
      \ 'directions': '',
      \ 'disease': '',
      \ 'divide': '',
      \ 'dizzy': '',
      \ 'dna': '',
      \ 'dog': '',
      \ 'dollar-sign': '',
      \ 'dolly': '',
      \ 'dolly-flatbed': '',
      \ 'donate': '',
      \ 'door-closed': '',
      \ 'door-open': '',
      \ 'dot-circle': '',
      \ 'dove': '',
      \ 'download': '',
      \ 'drafting-compass': '',
      \ 'dragon': '',
      \ 'draw-polygon': '',
      \ 'drum': '',
      \ 'drum-steelpan': '',
      \ 'drumstick-bite': '',
      \ 'dumbbell': '',
      \ 'dumpster': '',
      \ 'dumpster-fire': '',
      \ 'dungeon': '',
      \ 'edit': '',
      \ 'egg': '',
      \ 'eject': '',
      \ 'ellipsis-h': '',
      \ 'ellipsis-v': '',
      \ 'envelope': '',
      \ 'envelope-open': '',
      \ 'envelope-open-text': '',
      \ 'envelope-square': '',
      \ 'equals': '',
      \ 'eraser': '',
      \ 'ethernet': '',
      \ 'euro-sign': '',
      \ 'exchange-alt': '',
      \ 'exclamation': '',
      \ 'exclamation-circle': '',
      \ 'exclamation-triangle': '',
      \ 'expand': '',
      \ 'expand-alt': '',
      \ 'expand-arrows-alt': '',
      \ 'external-link-alt': '',
      \ 'external-link-square-alt': '',
      \ 'eye': '',
      \ 'eye-dropper': '',
      \ 'eye-slash': '',
      \ 'fan': '',
      \ 'fast-backward': '',
      \ 'fast-forward': '',
      \ 'faucet': '',
      \ 'fax': '',
      \ 'feather': '',
      \ 'feather-alt': '',
      \ 'female': '',
      \ 'fighter-jet': '',
      \ 'file': '',
      \ 'file-alt': '',
      \ 'file-archive': '',
      \ 'file-audio': '',
      \ 'file-code': '',
      \ 'file-contract': '',
      \ 'file-csv': '',
      \ 'file-download': '',
      \ 'file-excel': '',
      \ 'file-export': '',
      \ 'file-image': '',
      \ 'file-import': '',
      \ 'file-invoice': '',
      \ 'file-invoice-dollar': '',
      \ 'file-medical': '',
      \ 'file-medical-alt': '',
      \ 'file-pdf': '',
      \ 'file-powerpoint': '',
      \ 'file-prescription': '',
      \ 'file-signature': '',
      \ 'file-upload': '',
      \ 'file-video': '',
      \ 'file-word': '',
      \ 'fill': '',
      \ 'fill-drip': '',
      \ 'film': '',
      \ 'filter': '',
      \ 'fingerprint': '',
      \ 'fire': '',
      \ 'fire-alt': '',
      \ 'fire-extinguisher': '',
      \ 'first-aid': '',
      \ 'fish': '',
      \ 'fist-raised': '',
      \ 'flag': '',
      \ 'flag-checkered': '',
      \ 'flag-usa': '',
      \ 'flask': '',
      \ 'flushed': '',
      \ 'folder': '',
      \ 'folder-minus': '',
      \ 'folder-open': '',
      \ 'folder-plus': '',
      \ 'font': '',
      \ 'football-ball': '',
      \ 'forward': '',
      \ 'frog': '',
      \ 'frown': '',
      \ 'frown-open': '',
      \ 'funnel-dollar': '',
      \ 'futbol': '',
      \ 'gamepad': '',
      \ 'gas-pump': '',
      \ 'gavel': '',
      \ 'gem': '',
      \ 'genderless': '',
      \ 'ghost': '',
      \ 'gift': '',
      \ 'gifts': '',
      \ 'glass-cheers': '',
      \ 'glass-martini': '',
      \ 'glass-martini-alt': '',
      \ 'glass-whiskey': '',
      \ 'glasses': '',
      \ 'globe': '',
      \ 'globe-africa': '',
      \ 'globe-americas': '',
      \ 'globe-asia': '',
      \ 'globe-europe': '',
      \ 'golf-ball': '',
      \ 'gopuram': '',
      \ 'graduation-cap': '',
      \ 'greater-than': '',
      \ 'greater-than-equal': '',
      \ 'grimace': '',
      \ 'grin': '',
      \ 'grin-alt': '',
      \ 'grin-beam': '',
      \ 'grin-beam-sweat': '',
      \ 'grin-hearts': '',
      \ 'grin-squint': '',
      \ 'grin-squint-tears': '',
      \ 'grin-stars': '',
      \ 'grin-tears': '',
      \ 'grin-tongue': '',
      \ 'grin-tongue-squint': '',
      \ 'grin-tongue-wink': '',
      \ 'grin-wink': '',
      \ 'grip-horizontal': '',
      \ 'grip-lines': '',
      \ 'grip-lines-vertical': '',
      \ 'grip-vertical': '',
      \ 'guitar': '',
      \ 'h-square': '',
      \ 'hamburger': '',
      \ 'hammer': '',
      \ 'hamsa': '',
      \ 'hand-holding': '',
      \ 'hand-holding-heart': '',
      \ 'hand-holding-medical': '',
      \ 'hand-holding-usd': '',
      \ 'hand-holding-water': '',
      \ 'hand-lizard': '',
      \ 'hand-middle-finger': '',
      \ 'hand-paper': '',
      \ 'hand-peace': '',
      \ 'hand-point-down': '',
      \ 'hand-point-left': '',
      \ 'hand-point-right': '',
      \ 'hand-point-up': '',
      \ 'hand-pointer': '',
      \ 'hand-rock': '',
      \ 'hand-scissors': '',
      \ 'hand-sparkles': '',
      \ 'hand-spock': '',
      \ 'hands': '',
      \ 'hands-helping': '',
      \ 'hands-wash': '',
      \ 'handshake': '',
      \ 'handshake-alt-slash': '',
      \ 'handshake-slash': '',
      \ 'hanukiah': '',
      \ 'hard-hat': '',
      \ 'hashtag': '',
      \ 'hat-cowboy': '',
      \ 'hat-cowboy-side': '',
      \ 'hat-wizard': '',
      \ 'hdd': '',
      \ 'head-side-cough': '',
      \ 'head-side-cough-slash': '',
      \ 'head-side-mask': '',
      \ 'head-side-virus': '',
      \ 'heading': '',
      \ 'headphones': '',
      \ 'headphones-alt': '',
      \ 'headset': '',
      \ 'heart': '',
      \ 'heart-broken': '',
      \ 'heartbeat': '',
      \ 'helicopter': '',
      \ 'highlighter': '',
      \ 'hiking': '',
      \ 'hippo': '',
      \ 'history': '',
      \ 'hockey-puck': '',
      \ 'holly-berry': '',
      \ 'home': '',
      \ 'horse': '',
      \ 'horse-head': '',
      \ 'hospital': '',
      \ 'hospital-alt': '',
      \ 'hospital-symbol': '',
      \ 'hospital-user': '',
      \ 'hot-tub': '',
      \ 'hotdog': '',
      \ 'hotel': '',
      \ 'hourglass': '',
      \ 'hourglass-end': '',
      \ 'hourglass-half': '',
      \ 'hourglass-start': '',
      \ 'house-damage': '',
      \ 'house-user': '',
      \ 'hryvnia': '',
      \ 'i-cursor': '',
      \ 'ice-cream': '',
      \ 'icicles': '',
      \ 'icons': '',
      \ 'id-badge': '',
      \ 'id-card': '',
      \ 'id-card-alt': '',
      \ 'igloo': '',
      \ 'image': '',
      \ 'images': '',
      \ 'inbox': '',
      \ 'indent': '',
      \ 'industry': '',
      \ 'infinity': '',
      \ 'info': '',
      \ 'info-circle': '',
      \ 'italic': '',
      \ 'jedi': '',
      \ 'joint': '',
      \ 'journal-whills': '',
      \ 'kaaba': '',
      \ 'key': '',
      \ 'keyboard': '',
      \ 'khanda': '',
      \ 'kiss': '',
      \ 'kiss-beam': '',
      \ 'kiss-wink-heart': '',
      \ 'kiwi-bird': '',
      \ 'landmark': '',
      \ 'language': '',
      \ 'laptop': '',
      \ 'laptop-code': '',
      \ 'laptop-house': '',
      \ 'laptop-medical': '',
      \ 'laugh': '',
      \ 'laugh-beam': '',
      \ 'laugh-squint': '',
      \ 'laugh-wink': '',
      \ 'layer-group': '',
      \ 'leaf': '',
      \ 'lemon': '',
      \ 'less-than': '',
      \ 'less-than-equal': '',
      \ 'level-down-alt': '',
      \ 'level-up-alt': '',
      \ 'life-ring': '',
      \ 'lightbulb': '',
      \ 'link': '',
      \ 'lira-sign': '',
      \ 'list': '',
      \ 'list-alt': '',
      \ 'list-ol': '',
      \ 'list-ul': '',
      \ 'location-arrow': '',
      \ 'lock': '',
      \ 'lock-open': '',
      \ 'long-arrow-alt-down': '',
      \ 'long-arrow-alt-left': '',
      \ 'long-arrow-alt-right': '',
      \ 'long-arrow-alt-up': '',
      \ 'low-vision': '',
      \ 'luggage-cart': '',
      \ 'lungs': '',
      \ 'lungs-virus': '',
      \ 'magic': '',
      \ 'magnet': '',
      \ 'mail-bulk': '',
      \ 'male': '',
      \ 'map': '',
      \ 'map-marked': '',
      \ 'map-marked-alt': '',
      \ 'map-marker': '',
      \ 'map-marker-alt': '',
      \ 'map-pin': '',
      \ 'map-signs': '',
      \ 'marker': '',
      \ 'mars': '',
      \ 'mars-double': '',
      \ 'mars-stroke': '',
      \ 'mars-stroke-h': '',
      \ 'mars-stroke-v': '',
      \ 'mask': '',
      \ 'medal': '',
      \ 'medkit': '',
      \ 'meh': '',
      \ 'meh-blank': '',
      \ 'meh-rolling-eyes': '',
      \ 'memory': '',
      \ 'menorah': '',
      \ 'mercury': '',
      \ 'meteor': '',
      \ 'microchip': '',
      \ 'microphone': '',
      \ 'microphone-alt': '',
      \ 'microphone-alt-slash': '',
      \ 'microphone-slash': '',
      \ 'microscope': '',
      \ 'minus': '',
      \ 'minus-circle': '',
      \ 'minus-square': '',
      \ 'mitten': '',
      \ 'mobile': '',
      \ 'mobile-alt': '',
      \ 'money-bill': '',
      \ 'money-bill-alt': '',
      \ 'money-bill-wave': '',
      \ 'money-bill-wave-alt': '',
      \ 'money-check': '',
      \ 'money-check-alt': '',
      \ 'monument': '',
      \ 'moon': '',
      \ 'mortar-pestle': '',
      \ 'mosque': '',
      \ 'motorcycle': '',
      \ 'mountain': '',
      \ 'mouse': '',
      \ 'mouse-pointer': '',
      \ 'mug-hot': '',
      \ 'music': '',
      \ 'network-wired': '',
      \ 'neuter': '',
      \ 'newspaper': '',
      \ 'not-equal': '',
      \ 'notes-medical': '',
      \ 'object-group': '',
      \ 'object-ungroup': '',
      \ 'oil-can': '',
      \ 'om': '',
      \ 'otter': '',
      \ 'outdent': '',
      \ 'pager': '',
      \ 'paint-brush': '',
      \ 'paint-roller': '',
      \ 'palette': '',
      \ 'pallet': '',
      \ 'paper-plane': '',
      \ 'paperclip': '',
      \ 'parachute-box': '',
      \ 'paragraph': '',
      \ 'parking': '',
      \ 'passport': '',
      \ 'pastafarianism': '',
      \ 'paste': '',
      \ 'pause': '',
      \ 'pause-circle': '',
      \ 'paw': '',
      \ 'peace': '',
      \ 'pen': '',
      \ 'pen-alt': '',
      \ 'pen-fancy': '',
      \ 'pen-nib': '',
      \ 'pen-square': '',
      \ 'pencil-alt': '',
      \ 'pencil-ruler': '',
      \ 'people-arrows': '',
      \ 'people-carry': '',
      \ 'pepper-hot': '',
      \ 'percent': '',
      \ 'percentage': '',
      \ 'person-booth': '',
      \ 'phone': '',
      \ 'phone-alt': '',
      \ 'phone-slash': '',
      \ 'phone-square': '',
      \ 'phone-square-alt': '',
      \ 'phone-volume': '',
      \ 'photo-video': '',
      \ 'piggy-bank': '',
      \ 'pills': '',
      \ 'pizza-slice': '',
      \ 'place-of-worship': '',
      \ 'plane': '',
      \ 'plane-arrival': '',
      \ 'plane-departure': '',
      \ 'plane-slash': '',
      \ 'play': '',
      \ 'play-circle': '',
      \ 'plug': '',
      \ 'plus': '',
      \ 'plus-circle': '',
      \ 'plus-square': '',
      \ 'podcast': '',
      \ 'poll': '',
      \ 'poll-h': '',
      \ 'poo': '',
      \ 'poo-storm': '',
      \ 'poop': '',
      \ 'portrait': '',
      \ 'pound-sign': '',
      \ 'power-off': '',
      \ 'pray': '',
      \ 'praying-hands': '',
      \ 'prescription': '',
      \ 'prescription-bottle': '',
      \ 'prescription-bottle-alt': '',
      \ 'print': '',
      \ 'procedures': '',
      \ 'project-diagram': '',
      \ 'pump-medical': '',
      \ 'pump-soap': '',
      \ 'puzzle-piece': '',
      \ 'qrcode': '',
      \ 'question': '',
      \ 'question-circle': '',
      \ 'quidditch': '',
      \ 'quote-left': '',
      \ 'quote-right': '',
      \ 'quran': '',
      \ 'radiation': '',
      \ 'radiation-alt': '',
      \ 'rainbow': '',
      \ 'random': '',
      \ 'receipt': '',
      \ 'record-vinyl': '',
      \ 'recycle': '',
      \ 'redo': '',
      \ 'redo-alt': '',
      \ 'registered': '',
      \ 'remove-format': '',
      \ 'reply': '',
      \ 'reply-all': '',
      \ 'republican': '',
      \ 'restroom': '',
      \ 'retweet': '',
      \ 'ribbon': '',
      \ 'ring': '',
      \ 'road': '',
      \ 'robot': '',
      \ 'rocket': '',
      \ 'route': '',
      \ 'rss': '',
      \ 'rss-square': '',
      \ 'ruble-sign': '',
      \ 'ruler': '',
      \ 'ruler-combined': '',
      \ 'ruler-horizontal': '',
      \ 'ruler-vertical': '',
      \ 'running': '',
      \ 'rupee-sign': '',
      \ 'sad-cry': '',
      \ 'sad-tear': '',
      \ 'satellite': '',
      \ 'satellite-dish': '',
      \ 'save': '',
      \ 'school': '',
      \ 'screwdriver': '',
      \ 'scroll': '',
      \ 'sd-card': '',
      \ 'search': '',
      \ 'search-dollar': '',
      \ 'search-location': '',
      \ 'search-minus': '',
      \ 'search-plus': '',
      \ 'seedling': '',
      \ 'server': '',
      \ 'shapes': '',
      \ 'share': '',
      \ 'share-alt': '',
      \ 'share-alt-square': '',
      \ 'share-square': '',
      \ 'shekel-sign': '',
      \ 'shield-alt': '',
      \ 'shield-virus': '',
      \ 'ship': '',
      \ 'shipping-fast': '',
      \ 'shoe-prints': '',
      \ 'shopping-bag': '',
      \ 'shopping-basket': '',
      \ 'shopping-cart': '',
      \ 'shower': '',
      \ 'shuttle-van': '',
      \ 'sign': '',
      \ 'sign-in-alt': '',
      \ 'sign-language': '',
      \ 'sign-out-alt': '',
      \ 'signal': '',
      \ 'signature': '',
      \ 'sim-card': '',
      \ 'sink': '',
      \ 'sitemap': '',
      \ 'skating': '',
      \ 'skiing': '',
      \ 'skiing-nordic': '',
      \ 'skull': '',
      \ 'skull-crossbones': '',
      \ 'slash': '',
      \ 'sleigh': '',
      \ 'sliders-h': '',
      \ 'smile': '',
      \ 'smile-beam': '',
      \ 'smile-wink': '',
      \ 'smog': '',
      \ 'smoking': '',
      \ 'smoking-ban': '',
      \ 'sms': '',
      \ 'snowboarding': '',
      \ 'snowflake': '',
      \ 'snowman': '',
      \ 'snowplow': '',
      \ 'soap': '',
      \ 'socks': '',
      \ 'solar-panel': '',
      \ 'sort': '',
      \ 'sort-alpha-down': '',
      \ 'sort-alpha-down-alt': '',
      \ 'sort-alpha-up': '',
      \ 'sort-alpha-up-alt': '',
      \ 'sort-amount-down': '',
      \ 'sort-amount-down-alt': '',
      \ 'sort-amount-up': '',
      \ 'sort-amount-up-alt': '',
      \ 'sort-down': '',
      \ 'sort-numeric-down': '',
      \ 'sort-numeric-down-alt': '',
      \ 'sort-numeric-up': '',
      \ 'sort-numeric-up-alt': '',
      \ 'sort-up': '',
      \ 'spa': '',
      \ 'space-shuttle': '',
      \ 'spell-check': '',
      \ 'spider': '',
      \ 'spinner': '',
      \ 'splotch': '',
      \ 'spray-can': '',
      \ 'square': '',
      \ 'square-full': '',
      \ 'square-root-alt': '',
      \ 'stamp': '',
      \ 'star': '',
      \ 'star-and-crescent': '',
      \ 'star-half': '',
      \ 'star-half-alt': '',
      \ 'star-of-david': '',
      \ 'star-of-life': '',
      \ 'step-backward': '',
      \ 'step-forward': '',
      \ 'stethoscope': '',
      \ 'sticky-note': '',
      \ 'stop': '',
      \ 'stop-circle': '',
      \ 'stopwatch': '',
      \ 'stopwatch-20': '',
      \ 'store': '',
      \ 'store-alt': '',
      \ 'store-alt-slash': '',
      \ 'store-slash': '',
      \ 'stream': '',
      \ 'street-view': '',
      \ 'strikethrough': '',
      \ 'stroopwafel': '',
      \ 'subscript': '',
      \ 'subway': '',
      \ 'suitcase': '',
      \ 'suitcase-rolling': '',
      \ 'sun': '',
      \ 'superscript': '',
      \ 'surprise': '',
      \ 'swatchbook': '',
      \ 'swimmer': '',
      \ 'swimming-pool': '',
      \ 'synagogue': '',
      \ 'sync': '',
      \ 'sync-alt': '',
      \ 'syringe': '',
      \ 'table': '',
      \ 'table-tennis': '',
      \ 'tablet': '',
      \ 'tablet-alt': '',
      \ 'tablets': '',
      \ 'tachometer-alt': '',
      \ 'tag': '',
      \ 'tags': '',
      \ 'tape': '',
      \ 'tasks': '',
      \ 'taxi': '',
      \ 'teeth': '',
      \ 'teeth-open': '',
      \ 'temperature-high': '',
      \ 'temperature-low': '',
      \ 'tenge': '',
      \ 'terminal': '',
      \ 'text-height': '',
      \ 'text-width': '',
      \ 'th': '',
      \ 'th-large': '',
      \ 'th-list': '',
      \ 'theater-masks': '',
      \ 'thermometer': '',
      \ 'thermometer-empty': '',
      \ 'thermometer-full': '',
      \ 'thermometer-half': '',
      \ 'thermometer-quarter': '',
      \ 'thermometer-three-quarters': '',
      \ 'thumbs-down': '',
      \ 'thumbs-up': '',
      \ 'thumbtack': '',
      \ 'ticket-alt': '',
      \ 'times': '',
      \ 'times-circle': '',
      \ 'tint': '',
      \ 'tint-slash': '',
      \ 'tired': '',
      \ 'toggle-off': '',
      \ 'toggle-on': '',
      \ 'toilet': '',
      \ 'toilet-paper': '',
      \ 'toilet-paper-slash': '',
      \ 'toolbox': '',
      \ 'tools': '',
      \ 'tooth': '',
      \ 'torah': '',
      \ 'torii-gate': '',
      \ 'tractor': '',
      \ 'trademark': '',
      \ 'traffic-light': '',
      \ 'trailer': '',
      \ 'train': '',
      \ 'tram': '',
      \ 'transgender': '',
      \ 'transgender-alt': '',
      \ 'trash': '',
      \ 'trash-alt': '',
      \ 'trash-restore': '',
      \ 'trash-restore-alt': '',
      \ 'tree': '',
      \ 'trophy': '',
      \ 'truck': '',
      \ 'truck-loading': '',
      \ 'truck-monster': '',
      \ 'truck-moving': '',
      \ 'truck-pickup': '',
      \ 'tshirt': '',
      \ 'tty': '',
      \ 'tv': '',
      \ 'umbrella': '',
      \ 'umbrella-beach': '',
      \ 'underline': '',
      \ 'undo': '',
      \ 'undo-alt': '',
      \ 'universal-access': '',
      \ 'university': '',
      \ 'unlink': '',
      \ 'unlock': '',
      \ 'unlock-alt': '',
      \ 'upload': '',
      \ 'user': '',
      \ 'user-alt': '',
      \ 'user-alt-slash': '',
      \ 'user-astronaut': '',
      \ 'user-check': '',
      \ 'user-circle': '',
      \ 'user-clock': '',
      \ 'user-cog': '',
      \ 'user-edit': '',
      \ 'user-friends': '',
      \ 'user-graduate': '',
      \ 'user-injured': '',
      \ 'user-lock': '',
      \ 'user-md': '',
      \ 'user-minus': '',
      \ 'user-ninja': '',
      \ 'user-nurse': '',
      \ 'user-plus': '',
      \ 'user-secret': '',
      \ 'user-shield': '',
      \ 'user-slash': '',
      \ 'user-tag': '',
      \ 'user-tie': '',
      \ 'user-times': '',
      \ 'users': '',
      \ 'users-cog': '',
      \ 'users-slash': '',
      \ 'utensil-spoon': '',
      \ 'utensils': '',
      \ 'vector-square': '',
      \ 'venus': '',
      \ 'venus-double': '',
      \ 'venus-mars': '',
      \ 'vest': '',
      \ 'vest-patches': '',
      \ 'vial': '',
      \ 'vials': '',
      \ 'video': '',
      \ 'video-slash': '',
      \ 'vihara': '',
      \ 'virus': '',
      \ 'virus-slash': '',
      \ 'viruses': '',
      \ 'voicemail': '',
      \ 'volleyball-ball': '',
      \ 'volume-down': '',
      \ 'volume-mute': '',
      \ 'volume-off': '',
      \ 'volume-up': '',
      \ 'vote-yea': '',
      \ 'vr-cardboard': '',
      \ 'walking': '',
      \ 'wallet': '',
      \ 'warehouse': '',
      \ 'water': '',
      \ 'wave-square': '',
      \ 'weight': '',
      \ 'weight-hanging': '',
      \ 'wheelchair': '',
      \ 'wifi': '',
      \ 'wind': '',
      \ 'window-close': '',
      \ 'window-maximize': '',
      \ 'window-minimize': '',
      \ 'window-restore': '',
      \ 'wine-bottle': '',
      \ 'wine-glass': '',
      \ 'wine-glass-alt': '',
      \ 'won-sign': '',
      \ 'wrench': '',
      \ 'x-ray': '',
      \ 'yen-sign': '',
      \ 'yin-yang': '',
      \ }
for [s:k, s:v] in items(s:fontawesome)
  let s:re = ''
  " first char is not a number
  if index(map(range(10), {v -> v . ''}), s:k[0]) == -1
    if s:k[-4:] ==# '-alt'
      let s:name = s:k[:-5] . '\*'
    else
      let s:name = s:k . '\>'
    endif
    let s:re .= '\\fa' . substitute(s:name, '\%(^\|-\)\(.\)', '\u\1', 'g') . '\|'
  endif
  let s:re .= '\\faIcon\%\(\[\%\(regular\|solid\)]\|\){' . s:k . '}'
  if s:k[-4:] ==# '-alt'
    let s:re .= '\\faIcon\*\%\(\[\%\(regular\|solid\)]\|\){' . s:k[:-5] . '}'
  endif
  execute "syn match texCmd '" . s:re . "' conceal cchar=" . s:v
endfor
" ex: tabstop=2 shiftwidth=2

[Freed-Wu]

I temporarily realize a plugin to do this work for me. If you realize it in vimtex, please apply this issue, and I'll solve the potential conflict.

[lervag]

I've added support for the fontawesome5 package now. Please test.

Also, thanks a bunch for providing a solution along with the issue report. I've more or less copied it, although I did found a few minor mistakes in the regexes. I also made some further improvements, I believe. I'll let you be the judge :)

[Freed-Wu]

Works great:

I have an advice:

Like https://github.com/lambdalisue/nerdfont.vim#contribution and https://github.com/voldikss/vim-browser-search/blob/master/assets/json/engines.json.
How about use a json to save the icons of fontawesome, then use
json_decode(join(readfile(s:json_path), ''))?

good

Because these icons are only data, which use an independent data exchange format may be more reasonable.
Json can also be processed by other programs, such as json can be sorted more easily by jq -S . if we want a sorted result?
or use other program to download data from the website and use the data to update the json if fontawesome add any new icons?

bad

decode a json will cost a little time

[lervag]

Thanks for the advice. I agree in principle that having the data separated from the code is better. However, in this specific case, I believe it will bring little to no real advantage at a cost of slightly higher complexity. As a pragmatic plugin developer with not too much time, I'll therefore not do this. But I would be willing to consider a PR for something like this, if anyone (you) would be willing to help.

Notice that the order of the syntax match statements is important, which is why I changed from the dictionary to a list. Specifically, the starred variant rules must come after the unstarred variants. Thus, the json_decode should either read a list or be sorted after reading.

[Freed-Wu]

consider a PR for something like this

OK, I have tested a PR can work.

[lervag]

Cool! For future reference: #2528.