[ { "path": ".editorconfig", "content": "root = true\n\n[*]\ncharset = utf-8\nindent_style = space\nindent_size = 2\nend_of_line = lf\ninsert_final_newline = true\ntrim_trailing_whitespace = true\n" }, { "path": ".github/FUNDING.yml", "content": "open_collective: front-end-checklist\ngithub: thedaviddias\nthanks_dev: thedaviddias\n" }, { "path": ".github/ISSUE_TEMPLATE.md", "content": "" }, { "path": ".github/PULL_REQUEST_TEMPLATE.md", "content": "\n\n**Fixes**: #\n\nšŸšØ Please review the [guidelines for contributing](CONTRIBUTING.md) and our [code of conduct](../CODE_OF_CONDUCT.md) to this repository. šŸšØ\n**Please complete these steps and check these boxes (by putting an x inside the brackets) before filing your PR:**\n\n- [ ] Check the commit's or even all commits' message styles matches our requested structure.\n- [ ] Check your code additions will fail neither code linting checks nor unit test.\n\n#### Short description of what this resolves:\n\n\n#### Proposed changes:\n\n-\n-\n-\n\nšŸ‘ Thank you!\n" }, { "path": ".github/workflows/links-checker.yml", "content": "name: Links Checker\n\non:\n repository_dispatch:\n workflow_dispatch:\n schedule:\n - cron: '0 0 * * 1' # bi weekly on Monday\n\nenv:\n HUSKY: 0\n\njobs:\n links-checker:\n runs-on: ubuntu-latest\n name: Links Checker\n permissions:\n issues: write\n\n steps:\n - uses: actions/checkout@v4\n\n - name: Link Checker\n id: lychee\n uses: lycheeverse/lychee-action@v2.0.2\n with:\n args: --config ./lychee.toml --verbose --no-progress README.md\n fail: true\n\n - name: Create Issue From File\n if: env.exit_code != 0\n uses: peter-evans/create-issue-from-file@v5\n with:\n title: Link Checker Report\n content-filepath: ./lychee-out.md\n labels: report, automated issue\n" }, { "path": ".github/workflows/readme-check.yml", "content": "name: Readme Check\n\non:\n pull_request:\n paths:\n - 'README.md'\n\nenv:\n HUSKY: 0\n\njobs:\n readme-check:\n runs-on: ubuntu-latest\n name: Readme Check\n\n steps:\n - uses: actions/checkout@v4\n\n - name: Setup Node.js\n uses: actions/setup-node@v4\n with:\n node-version: '22'\n\n - name: Setup pnpm\n uses: pnpm/action-setup@v4\n with:\n version: 9\n\n - name: Install dependencies\n run: pnpm i\n\n - name: Check Markdown formatting\n run: pnpm format:check\n\n - name: Link Checker\n uses: lycheeverse/lychee-action@v2.0.2\n with:\n args: --config ./lychee.toml --verbose --no-progress README.md\n fail: true\n" }, { "path": ".github/workflows/stale.yml", "content": "name: 'Close stale issues and PRs'\n\non:\n schedule:\n - cron: '30 1 * * 6'\n workflow_dispatch:\n\npermissions:\n issues: write\n pull-requests: write\n\nenv:\n HUSKY: 0\n\njobs:\n stale:\n runs-on: ubuntu-latest\n\n steps:\n - uses: actions/stale@v8\n with:\n stale-issue-message: 'This issue has been automatically marked as stale because it has been open 40 days with no activity. Remove stale label or comment or this will be closed in 10 days. Thank you for your contributions!'\n stale-pr-message: 'This PR has been automatically marked as stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 10 days.'\n close-issue-message: 'This issue was closed because it has been stalled for 10 days with no activity. You can always contact the maintainers directly for more information.'\n close-pr-message: 'This PR was closed because it has been stalled for 10 days with no activity. You can always contact the maintainers directly for more information.'\n days-before-stale: 40\n days-before-pr-stale: 45\n days-before-close: 10\n exempt-issue-assignees: 'thedaviddias'\n exempt-pr-assignees: 'thedaviddias'\n exempt-all-pr-assignees: true\n stale-issue-label: 'stale'\n stale-pr-label: 'stale'\n exempt-pr-labels: 'keep-unstale,security,dependabot,wip,need-help'\n exempt-issue-labels: 'keep-unstale,security'\n close-issue-label: 'wontfix'\n" }, { "path": ".gitignore", "content": ".DS_Store\nnode_modules\n.lycheecache\nlychee-out.md\n" }, { "path": ".husky/pre-push", "content": "pnpm format:fix\n" }, { "path": ".markdownlint.json", "content": "{\n \"MD013\": false,\n \"MD024\": false,\n \"MD033\": false\n}\n" }, { "path": ".prettierrc", "content": "{\n \"trailingComma\": \"none\",\n \"tabWidth\": 2,\n \"semi\": true,\n \"singleQuote\": true,\n \"printWidth\": 150,\n \"endOfLine\": \"lf\",\n \"overrides\": [\n {\n \"files\": \"*.md\",\n \"options\": {\n \"htmlWhitespaceSensitivity\": \"ignore\",\n \"proseWrap\": \"preserve\",\n \"embeddedLanguageFormatting\": \"off\"\n }\n }\n ]\n}\n" }, { "path": "CODE_OF_CONDUCT.md", "content": "# Contributor Covenant Code of Conduct\n\n## Our Pledge\n\nIn the interest of fostering an open and welcoming environment, we as contributors and maintainers pledge to make participation in our project and our community a harassment-free experience for everyone, regardless of age, body size, disability, ethnicity, gender identity and expression, level of experience, nationality, personal appearance, race, religion, or sexual identity and orientation.\n\n## Our Standards\n\nExamples of behavior that contributes to creating a positive environment include:\n\n* Using welcoming and inclusive language\n* Being respectful of differing viewpoints and experiences\n* Gracefully accepting constructive criticism\n* Focusing on what is best for the community\n* Showing empathy towards other community members\n\nExamples of unacceptable behavior by participants include:\n\n* The use of sexualized language or imagery and unwelcome sexual attention or advances\n* Trolling, insulting/derogatory comments, and personal or political attacks\n* Public or private harassment\n* Publishing others' private information, such as a physical or electronic address, without explicit permission\n* Other conduct which could reasonably be considered inappropriate in a professional setting\n\n## Our Responsibilities\n\nProject maintainers are responsible for clarifying the standards of acceptable behavior and are expected to take appropriate and fair corrective action in response to any instances of unacceptable behavior.\n\nProject maintainers have the right and responsibility to remove, edit, or reject comments, commits, code, wiki edits, issues, and other contributions that are not aligned to this Code of Conduct, or to ban temporarily or permanently any contributor for other behaviors that they deem inappropriate, threatening, offensive, or harmful.\n\n## Scope\n\nThis Code of Conduct applies both within project spaces and in public spaces when an individual is representing the project or its community. Examples of representing a project or community include using an official project e-mail address, posting via an official social media account, or acting as an appointed representative at an online or offline event. Representation of a project may be further defined and clarified by project maintainers.\n\n## Enforcement\n\nInstances of abusive, harassing, or otherwise unacceptable behavior may be reported by contacting the project team at thedaviddias@gmail.com. The project team will review and investigate all complaints, and will respond in a way that it deems appropriate to the circumstances. The project team is obligated to maintain confidentiality with regard to the reporter of an incident. Further details of specific enforcement policies may be posted separately.\n\nProject maintainers who do not follow or enforce the Code of Conduct in good faith may face temporary or permanent repercussions as determined by other members of the project's leadership.\n\n## Attribution\n\nThis Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4, available at [http://contributor-covenant.org/version/1/4][version]\n\n[homepage]: http://contributor-covenant.org\n[version]: http://contributor-covenant.org/version/1/4/\n" }, { "path": "CONTRIBUTING.md", "content": "# Contribute\n\n## Introduction\n\nFirst, thank you for considering contributing to front-end-checklist! It's people like you that make the open source community such a great community! šŸ˜Š\n\nWe welcome any type of contribution, not only code. You can help with\n- **QA**: file bug reports, the more details you can give the better (e.g. screenshots with the console open)\n- **Marketing**: writing blog posts, howto's, printing stickers, ...\n- **Community**: presenting the project at meetups, organizing a dedicated meetup for the local community, ...\n- **Code**: take a look at the [open issues](https://github.com/thedaviddias/Front-End-Checklist/issues). Even if you can't write code, commenting on them, showing that you care about a given issue matters. It helps us triage them.\n- **Money**: we welcome financial contributions in full transparency on our [open collective](https://opencollective.com/front-end-checklist).\n\n## Your First Contribution\n\nWorking on your first Pull Request? You can learn how from this *free* series, [How to Contribute to an Open Source Project on GitHub](https://app.egghead.io/playlists/how-to-contribute-to-an-open-source-project-on-github).\n\n## Submitting code\n\nAny code change should be submitted as a pull request. The description should explain what the code does and give steps to execute it. The pull request should also contain tests.\n\n## Code review process\n\nThe bigger the pull request, the longer it will take to review and merge. Try to break down large pull requests in smaller chunks that are easier to review and merge.\nIt is also always helpful to have some context for your pull request. What was the purpose? Why does it matter to you?\n\n## Financial contributions\n\nWe also welcome financial contributions in full transparency on our [open collective](https://opencollective.com/front-end-checklist).\nAnyone can file an expense. If the expense makes sense for the development of the community, it will be \"merged\" in the ledger of our open collective by the core contributors and the person who filed the expense will be reimbursed.\n\n## Questions\n\nIf you have any questions, create an [issue](https://github.com/thedaviddias/Front-End-Checklist/issues) (protip: do a quick search first to see if someone else didn't ask the same question before!).\nYou can also reach us at hello@front-end-checklist.opencollective.com.\n\n## Credits\n\n### Contributors\n\nThank you to all the people who have already contributed to front-end-checklist!\n\n\n\n### Backers\n\nThank you to all our backers! [[Become a backer](https://opencollective.com/front-end-checklist#backer)]\n\n\n\n\n### Sponsors\n\nThank you to all our sponsors! (please ask your company to also support this open source project by [becoming a sponsor](https://opencollective.com/front-end-checklist#sponsor))\n\n\n\n" }, { "path": "LICENSE", "content": "CC0 1.0 Universal\n\nStatement of Purpose\n\nThe laws of most jurisdictions throughout the world automatically confer\nexclusive Copyright and Related Rights (defined below) upon the creator and\nsubsequent owner(s) (each and all, an \"owner\") of an original work of\nauthorship and/or a database (each, a \"Work\").\n\nCertain owners wish to permanently relinquish those rights to a Work for the\npurpose of contributing to a commons of creative, cultural and scientific\nworks (\"Commons\") that the public can reliably and without fear of later\nclaims of infringement build upon, modify, incorporate in other works, reuse\nand redistribute as freely as possible in any form whatsoever and for any\npurposes, including without limitation commercial purposes. These owners may\ncontribute to the Commons to promote the ideal of a free culture and the\nfurther production of creative, cultural and scientific works, or to gain\nreputation or greater distribution for their Work in part through the use and\nefforts of others.\n\nFor these and/or other purposes and motivations, and without any expectation\nof additional consideration or compensation, the person associating CC0 with a\nWork (the \"Affirmer\"), to the extent that he or she is an owner of Copyright\nand Related Rights in the Work, voluntarily elects to apply CC0 to the Work\nand publicly distribute the Work under its terms, with knowledge of his or her\nCopyright and Related Rights in the Work and the meaning and intended legal\neffect of CC0 on those rights.\n\n1. Copyright and Related Rights. A Work made available under CC0 may be\nprotected by copyright and related or neighboring rights (\"Copyright and\nRelated Rights\"). Copyright and Related Rights include, but are not limited\nto, the following:\n\n i. the right to reproduce, adapt, distribute, perform, display, communicate,\n and translate a Work;\n\n ii. moral rights retained by the original author(s) and/or performer(s);\n\n iii. publicity and privacy rights pertaining to a person's image or likeness\n depicted in a Work;\n\n iv. rights protecting against unfair competition in regards to a Work,\n subject to the limitations in paragraph 4(a), below;\n\n v. rights protecting the extraction, dissemination, use and reuse of data in\n a Work;\n\n vi. database rights (such as those arising under Directive 96/9/EC of the\n European Parliament and of the Council of 11 March 1996 on the legal\n protection of databases, and under any national implementation thereof,\n including any amended or successor version of such directive); and\n\n vii. other similar, equivalent or corresponding rights throughout the world\n based on applicable law or treaty, and any national implementations thereof.\n\n2. Waiver. To the greatest extent permitted by, but not in contravention of,\napplicable law, Affirmer hereby overtly, fully, permanently, irrevocably and\nunconditionally waives, abandons, and surrenders all of Affirmer's Copyright\nand Related Rights and associated claims and causes of action, whether now\nknown or unknown (including existing as well as future claims and causes of\naction), in the Work (i) in all territories worldwide, (ii) for the maximum\nduration provided by applicable law or treaty (including future time\nextensions), (iii) in any current or future medium and for any number of\ncopies, and (iv) for any purpose whatsoever, including without limitation\ncommercial, advertising or promotional purposes (the \"Waiver\"). Affirmer makes\nthe Waiver for the benefit of each member of the public at large and to the\ndetriment of Affirmer's heirs and successors, fully intending that such Waiver\nshall not be subject to revocation, rescission, cancellation, termination, or\nany other legal or equitable action to disrupt the quiet enjoyment of the Work\nby the public as contemplated by Affirmer's express Statement of Purpose.\n\n3. Public License Fallback. Should any part of the Waiver for any reason be\njudged legally invalid or ineffective under applicable law, then the Waiver\nshall be preserved to the maximum extent permitted taking into account\nAffirmer's express Statement of Purpose. In addition, to the extent the Waiver\nis so judged Affirmer hereby grants to each affected person a royalty-free,\nnon transferable, non sublicensable, non exclusive, irrevocable and\nunconditional license to exercise Affirmer's Copyright and Related Rights in\nthe Work (i) in all territories worldwide, (ii) for the maximum duration\nprovided by applicable law or treaty (including future time extensions), (iii)\nin any current or future medium and for any number of copies, and (iv) for any\npurpose whatsoever, including without limitation commercial, advertising or\npromotional purposes (the \"License\"). The License shall be deemed effective as\nof the date CC0 was applied by Affirmer to the Work. Should any part of the\nLicense for any reason be judged legally invalid or ineffective under\napplicable law, such partial invalidity or ineffectiveness shall not\ninvalidate the remainder of the License, and in such case Affirmer hereby\naffirms that he or she will not (i) exercise any of his or her remaining\nCopyright and Related Rights in the Work or (ii) assert any associated claims\nand causes of action with respect to the Work, in either case contrary to\nAffirmer's express Statement of Purpose.\n\n4. Limitations and Disclaimers.\n\n a. No trademark or patent rights held by Affirmer are waived, abandoned,\n surrendered, licensed or otherwise affected by this document.\n\n b. Affirmer offers the Work as-is and makes no representations or warranties\n of any kind concerning the Work, express, implied, statutory or otherwise,\n including without limitation warranties of title, merchantability, fitness\n for a particular purpose, non infringement, or the absence of latent or\n other defects, accuracy, or the present or absence of errors, whether or not\n discoverable, all to the greatest extent permissible under applicable law.\n\n c. Affirmer disclaims responsibility for clearing rights of other persons\n that may apply to the Work or any use thereof, including without limitation\n any person's Copyright and Related Rights in the Work. Further, Affirmer\n disclaims responsibility for obtaining any necessary consents, permissions\n or other rights required for any use of the Work.\n\n d. Affirmer understands and acknowledges that Creative Commons is not a\n party to this document and has no duty or obligation with respect to this\n CC0 or use of the Work.\n\nFor more information, please see\n\n" }, { "path": "README.md", "content": "# šŸ—‚ Front-End Checklist\n\nThe Front-End Checklist is an exhaustive list of all elements you need to have / to test before launching your website /\nHTML page to production.\n\n**Other Checklists:**\n\n- [šŸŽ® Front-End Performance Checklist](https://github.com/thedaviddias/Front-End-Performance-Checklist#---------front-end-performance-checklist-)\n- [šŸ’Ž Front-End Design Checklist](https://github.com/thedaviddias/Front-End-Design-Checklist#front-end-design-checklist)\n\n> [!TIP]\n> ā­ļø Dev-friendly UX patterns you wish you knew. šŸ‘‰ [UX Patterns for Devs](https://uxpatterns.dev/en) ā­ļø\n\n## šŸ“š Table of Contents\n\n- [How to use](#how-to-use)\n- [Head](#head)\n- [HTML](#html)\n- [Webfonts](#webfonts)\n- [CSS](#css)\n- [JavaScript](#javascript)\n- [Accessibility](#accessibility)\n\n## How to use?\n\n\n> [!IMPORTANT]\n> **Disclaimer:** This checklist is based on Front-End developers' years of experience, with additions from other open-source checklists.\n\n\nAll items in the **Front-End Checklist** are required for the majority of the projects, but some elements can be omitted\nor are not essential (in the case of an administration web app, you may not need RSS feed for example). We choose to use\n3 levels of flexibility:\n\n- ![Low][low_img] indicates that the item is recommended but can be omitted in certain situations.\n- ![Medium][medium_img] indicates that the item is highly recommended but can potentially be omitted in very specific\n cases. However, omitting these elements can negatively impact performance or SEO.\n- ![High][high_img] indicates that the item cannot be omitted under any circumstances. Removing these elements may\n result in page malfunctions or cause accessibility and SEO issues. Testing should prioritize these elements first.\n\nSome resources possess an emoticon to help you understand which type of content / help you may find on the checklist:\n\n- šŸ“–: documentation or article\n- šŸ› : online tool / testing tool\n- šŸ“¹: media or video content\n\n## Head\n\n\n> [!NOTE]\n> You can find [a list of everything](https://github.com/joshbuchea/HEAD) that could be found in the `` of an HTML document.\n\n\n### Meta tag\n\n- [ ] **Doctype:** ![High][high_img] The Doctype is HTML5 and is at the top of all your HTML pages.\n\n\n```html\n\n```\n\n\n- šŸ“–\n [Determining the character encoding - HTML5 W3C](https://www.w3.org/TR/html5/syntax.html#determining-the-character-encoding)\n\n_The next 2 meta tags (Charset and Viewport) need to come first in the head._\n\n- [ ] **Charset:** ![High][high_img] The charset (UTF-8) is declared correctly.\n\n\n```html\n\n\n```\n\n\n- [ ] **Viewport:** ![High][high_img] The viewport is declared correctly.\n\n\n```html\n\n\n```\n\n\n- [ ] **Title:** ![High][high_img] A title is used on all pages (SEO: Google calculates the pixel width of the characters used in the title, and it cuts off between 472 and 482 pixels. The average character limit would be around 55-characters).\n\n```html\n\nPage Title less than 55 characters\n```\n\n- šŸ“– [Title - HTML - MDN](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/title)\n- šŸ›  [SERP Snippet Generator](https://www.sistrix.com/serp-snippet-generator/)\n\n- [ ] **Description:** ![High][high_img] A meta description is provided, it is unique and doesn't possess more than 150\n characters.\n\n\n```html\n\n\n```\n\n\n- šŸ“–\n [Meta Description - HTML - MDN](https://developer.mozilla.org/en-US/docs/Learn/HTML/Introduction_to_HTML/The_head_metadata_in_HTML#Adding_an_author_and_description)\n\n- [ ] **Favicons:** ![Medium][medium_img] Each favicon has been created and displays correctly. If you have only a\n `favicon.ico`, put it at the root of your site. Normally you won't need to use any markup. However, it's still\n good practice to link to it using the example below. Today, **PNG format is recommended** over `.ico` format\n (dimensions: 32x32px).\n\n\n```html\n\n\n\n\n\n\n```\n\n\n- šŸ›  [Favicon Generator](https://www.favicon-generator.org/)\n- šŸ›  [RealFaviconGenerator](https://realfavicongenerator.net/)\n- šŸ“– [Favicon Cheat Sheet](https://github.com/audreyr/favicon-cheat-sheet)\n- šŸ“– [Favicons, Touch Icons, Tile Icons, etc. Which Do You Need? - CSS Tricks](https://css-tricks.com/favicon-quiz/)\n- šŸ“– [PNG favicons - caniuse](https://caniuse.com/link-icon-png)\n\n- [ ] **Apple Web App Meta:** ![Low][low_img] Apple meta-tags are present.\n\n\n```html\n\n\n\n\n\n\n\n\n\n```\n\n\n- šŸ“– [Configuring Web Applications](https://developer.apple.com/library/content/documentation/AppleApplications/Reference/SafariWebContent/ConfiguringWebApplications/ConfiguringWebApplications.html)\n- šŸ“– [Supported Meta Tags](https://developer.apple.com/library/content/documentation/AppleApplications/Reference/SafariHTMLRef/Articles/MetaTags.html)\n\n- [ ] **Windows Tiles:** ![Low][low_img] Windows tiles are present and linked.\n\n\n```html\n\n\n```\n\n\nMinimum required xml markup for the `browserconfig.xml` file is as follows:\n\n```xml\n\n\n \n \n \n \n \n \n \n \n\n```\n\n\n- šŸ“– [Browser configuration schema reference](https://learn.microsoft.com/en-us/previous-versions/windows/internet-explorer/ie-developer/platform-apis/dn320426(v=vs.85))\n\n\n- [ ] **Canonical:** ![Medium][medium_img] Use `rel=\"canonical\"` to avoid duplicate content.\n\n\n```html\n\n\n```\n\n\n- šŸ“–\n [Use canonical URLs - Search Console Help - Google Support](https://support.google.com/webmasters/answer/139066?hl=en)\n- šŸ“–\n [5 common mistakes with rel=canonical - Google Webmaster Blog](https://webmasters.googleblog.com/2013/04/5-common-mistakes-with-relcanonical.html)\n\n### HTML tags\n\n- [ ] **Language attribute:** ![High][high_img] The `lang` attribute of your website is specified and related to the\n language of the current page.\n\n```html\n\n```\n\n- [ ] **Direction attribute:** ![Medium][medium_img] The direction of lecture is specified on the html tag (It can be\n used on another HTML tag).\n\n```html\n\n \n\n```\n\n- šŸ“– [dir - HTML - MDN](https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/dir)\n\n- [ ] **Alternate language:** ![Low][low_img] The language tag of your website is specified and related to the language\n of the current page.\n\n\n```html\n\n```\n\n\n- [ ] **x-default:** ![Low][low_img] The language tag of your website for international landing pages.\n\n```html\n\n```\n\n- šŸ“– [x-default - Google](https://webmasters.googleblog.com/2013/04/x-default-hreflang-for-international-pages.html)\n\n- [ ] **Conditional comments:** ![Low][low_img] Conditional comments are present for IE if needed.\n\n- šŸ“–\n [About conditional comments (Internet Explorer) - MSDN - Microsoft]()\n\n- [ ] **RSS feed:** ![Low][low_img] If your project is a blog or has articles, an RSS link was provided.\n\n- [ ] **CSS Critical:** ![Medium][medium_img] The CSS critical (or \"above the fold\") collects all the CSS used to render\n the visible portion of the page. It is embedded before your principal CSS call and between `` in a\n single line (minified).\n\n- šŸ›  [Critical by Addy Osmani on GitHub](https://github.com/addyosmani/critical) automates this.\n\n- [ ] **CSS order:** ![High][high_img] All CSS files are loaded before any JavaScript files in the ``. (Except the\n case where sometimes JS files are loaded asynchronously on top of your page).\n\n### Social meta\n\nVisualize and generate automatically our social meta tags with [Meta Tags](https://metatags.io/)\n\n**_Facebook OG_** and **_Twitter Cards_** are, for any website, highly recommended. The other social media tags can be\nconsidered if you target a particular presence on those and want to ensure the display.\n\n- [ ] **Facebook Open Graph:** ![Low][low_img] All Facebook Open Graph (OG) are tested and no one is missing or with\n false information. Images need to be at least 600 x 315 pixels, although 1200 x 630 pixels is recommended.\n\n\n> [!NOTE]\n> Using `og:image:width` and `og:image:height` will specify the image dimensions to the crawler so that it can render the image immediately without having to asynchronously download and process it.\n\n\n\n```html\n\n\n\n\n\n\n\n\n\n\n```\n\n\n- šŸ“– [A Guide to Sharing for Webmasters](https://developers.facebook.com/docs/sharing/webmasters/)\n- šŸ“– [Best Practices - Sharing](https://developers.facebook.com/docs/sharing/best-practices/)\n- šŸ›  Test your page with the [Facebook OG testing](https://developers.facebook.com/tools/debug/)\n\n- [ ] **Twitter Card:** ![Low][low_img]\n\n\n```html\n\n\n\n\n\n\n\n```\n\n\n- šŸ“–\n [Getting started with cards ā€” Twitter Developers](https://developer.twitter.com/en/docs/tweets/optimize-with-cards/guides/getting-started)\n- šŸ›  Test your page with the [Twitter card validator](https://cards-dev.twitter.com/validator)\n\n**[ā¬† back to top](#-table-of-contents)**\n\n## HTML\n\n### Best practices\n\n- [ ] **HTML5 Semantic Elements:** ![High][high_img] HTML5 Semantic Elements are used appropriately (header, section,\n footer, main...).\n\n- šŸ“– [HTML Reference](http://htmlreference.io/)\n\n- [ ] **Error pages:** ![High][high_img] Error 404 page and 5xx exist. Remember that the 5xx error pages need to have\n their CSS integrated (no external call on the current server).\n\n- [ ] **Noopener:** ![Medium][medium_img] In case you are using external links with `target=\"_blank\"`, your link should\n have a `rel=\"noopener\"` attribute to prevent tab nabbing. If you need to support older versions of Firefox, use\n `rel=\"noopener noreferrer\"`.\n\n- šŸ“– [About rel=noopener](https://mathiasbynens.github.io/rel-noopener/)\n\n- [ ] **Clean up comments:** ![Low][low_img] Unnecessary code needs to be removed before sending the page to production.\n\n### HTML testing\n\n- [ ] **W3C compliant:** ![High][high_img] All pages need to be tested with the W3C validator to identify possible\n issues in the HTML code.\n\n- šŸ›  [W3C validator](https://validator.w3.org/)\n\n- [ ] **HTML Lint:** ![High][high_img] I use tools to help me analyze any issues I could have on my HTML code.\n\n- šŸ›  [Dirty markup](https://www.10bestdesign.com/dirtymarkup/)\n\n- šŸ›  [webhint](https://webhint.io/)\n\n- [ ] **Link checker:** ![High][high_img] There are no broken links in my page, verify that you don't have any 404\n error.\n\n- šŸ›  [W3C Link Checker](https://validator.w3.org/checklink)\n\n- [ ] **Adblockers test:** ![Medium][medium_img] Your website shows your content correctly with adblockers enabled (You\n can provide a message encouraging people to disable their adblocker).\n\n- šŸ“–\n [Use AdBlocking in your Dev Environment](https://andreicioara.com/use-adblocking-in-your-dev-environment-48db500d9b86)\n\n**[ā¬† back to top](#-table-of-contents)**\n\n---\n\n## Webfonts\n\n> [!NOTE]\n> Using web fonts may cause Flash Of Unstyled Text/Flash Of Invisible Text - consider having fallback fonts\n> and/or utilizing web font loaders to control behavior.\n\n- šŸ“– [Google Technical considerations about webfonts](https://developers.google.com/fonts/docs/technical_considerations)\n\n- [ ] **Webfont format:** ![High][high_img] WOFF, WOFF2 and TTF are supported by all modern browsers.\n\n- šŸ“– [WOFF - Web Open Font Format - Caniuse](https://caniuse.com/woff).\n- šŸ“– [WOFF 2.0 - Web Open Font Format - Caniuse](https://caniuse.com/woff2).\n- šŸ“– [TTF/OTF - TrueType and OpenType font support](https://caniuse.com/ttf)\n- šŸ“– [Using @font-face - CSS-Tricks](https://css-tricks.com/snippets/css/using-font-face/)\n\n- [ ] **Webfont size:** ![High][high_img] Webfont sizes don't exceed 2 MB (all variants included).\n\n- [ ] **Webfont loader:** ![Low][low_img] Control loading behavior with a webfont loader\n\n- šŸ›  [Typekit Web Font Loader](https://github.com/typekit/webfontloader)\n\n**[ā¬† back to top](#-table-of-contents)**\n\n---\n\n## CSS\n\n> **Notes:** Take a look at [CSS guidelines](https://cssguidelin.es/) and [Sass Guidelines](https://sass-guidelin.es/)\n> followed by most Front-End developers. If you have a doubt about CSS properties, you can visit\n> [CSS Reference](http://cssreference.io/). There is also a short [Code Guide](http://codeguide.co/) for consistency.\n\n- [ ] **Responsive Web Design:** ![High][high_img] The website is using responsive web design.\n- [ ] **CSS Print:** ![Medium][medium_img] A print stylesheet is provided and is correct on each page.\n- [ ] **Preprocessors:** ![Low][low_img] Your project is using a CSS preprocessor (e.g [Sass](http://sass-lang.com/),\n [Less](http://lesscss.org/), [Stylus](http://stylus-lang.com/)).\n- [ ] **Unique ID:** ![High][high_img] If IDs are used, they are unique to a page.\n- [ ] **Reset CSS:** ![High][high_img] A CSS reset (reset, normalize or reboot) is used and up to date. _(If you are\n using a CSS Framework like Bootstrap or Foundation, a Normalize is already included into it.)_\n\n- šŸ“– [Reset.css](https://meyerweb.com/eric/tools/css/reset/)\n- šŸ“– [Normalize.css](https://necolas.github.io/normalize.css/)\n- šŸ“– [Reboot](https://getbootstrap.com/docs/4.0/content/reboot/)\n\n- [ ] **JS prefix:** ![Low][low_img] All classes (or id- used in JavaScript files) begin with **js-** and are not styled\n into the CSS files.\n\n```html\n
\n \n
\n
\n```\n\n- [ ] **embedded or inline CSS:** ![High][high_img] Avoid at all cost embedding CSS in `