Index

CSS

  1. ::first-letter CSS pseudo-element selector
  2. ::placeholder CSS pseudo-element
  3. ::selection CSS pseudo-element
  4. :dir() CSS pseudo-class
  5. :has() CSS relational pseudo-class
  6. :in-range and :out-of-range CSS pseudo-classes
  7. :is() CSS pseudo-class
  8. :placeholder-shown CSS pseudo-class
  9. @font-face Web fonts
  10. Blending of HTML/SVG elements
  11. calc() as CSS unit value
  12. Case-insensitive CSS attribute selectors
  13. ch (character) unit
  14. CSS 2.1 selectors
  15. CSS ::marker pseudo-element
  16. CSS :any-link selector
  17. CSS :read-only and :read-write selectors
  18. CSS all property
  19. CSS Animation
  20. CSS Appearance
  21. CSS background-attachment
  22. CSS background-blend-mode
  23. CSS background-position edge offsets
  24. CSS background-repeat round and space
  25. CSS box-decoration-break
  26. CSS caret-color
  27. CSS clip-path property (for HTML)
  28. CSS color function
  29. CSS color-adjust
  30. CSS Conical Gradients
  31. CSS Containment
  32. CSS Counter Styles
  33. CSS Counters
  34. CSS Cross-Fade Function
  35. CSS currentColor value
  36. CSS Device Adaptation
  37. CSS display: contents
  38. CSS element() function
  39. CSS Exclusions Level 1
  40. CSS Feature Queries
  41. CSS Filter Effects
  42. CSS filter() function
  43. CSS first-line pseudo-element
  44. CSS Flexible Box Layout Module
  45. CSS Font Loading
  46. CSS font-feature-settings
  47. CSS font-rendering controls
  48. CSS font-size-adjust
  49. CSS font-stretch
  50. CSS font-variant-alternates
  51. CSS font-variant-numeric
  52. CSS Generated content for pseudo-elements
  53. CSS grab & grabbing cursors
  54. CSS Gradients
  55. CSS Grid Layout (level 1)
  56. CSS hanging-punctuation
  57. CSS Hyphenation
  58. CSS image-set
  59. CSS Initial Letter
  60. CSS initial value
  61. CSS inline-block
  62. CSS justify-content: space-evenly
  63. CSS Logical Properties
  64. CSS Masks
  65. CSS math functions min(), max() and clamp()
  66. CSS min/max-width/height
  67. CSS Motion Path
  68. CSS namespaces
  69. CSS outline properties
  70. CSS overflow property
  71. CSS overflow-anchor (Scroll Anchoring)
  72. CSS page-break properties
  73. CSS Paint API
  74. CSS position:fixed
  75. CSS position:sticky
  76. CSS Regions
  77. CSS Repeating Gradients
  78. CSS resize property
  79. CSS revert value
  80. CSS Scroll Snap
  81. CSS Shapes Level 1
  82. CSS Subgrid
  83. CSS Table display
  84. CSS text-indent
  85. CSS text-justify
  86. CSS text-orientation
  87. CSS touch-action property
  88. CSS unset value
  89. CSS user-select: none
  90. CSS Variables (Custom Properties)
  91. CSS widows & orphans
  92. CSS will-change property
  93. CSS writing-mode property
  94. CSS3 2D Transforms
  95. CSS3 3D Transforms
  96. CSS3 attr() function for all properties
  97. CSS3 Background-image options
  98. CSS3 Border images
  99. CSS3 Border-radius (rounded corners)
  100. CSS3 Box-shadow
  101. CSS3 Box-sizing
  102. CSS3 Colors
  103. CSS3 Cursors (original values)
  104. CSS3 Cursors: zoom-in & zoom-out
  105. CSS3 font-kerning
  106. CSS3 image-orientation
  107. CSS3 Media Queries
  108. CSS3 Multiple backgrounds
  109. CSS3 Multiple column layout
  110. CSS3 object-fit/object-position
  111. CSS3 Opacity
  112. CSS3 Overflow-wrap
  113. CSS3 selectors
  114. CSS3 tab-size
  115. CSS3 text-align-last
  116. CSS3 Text-overflow
  117. CSS3 Text-shadow
  118. CSS3 Transitions
  119. CSS3 word-break
  120. CSSOM Scroll-behavior
  121. display: flow-root
  122. display: run-in
  123. Font unicode-range subsetting
  124. gap property for Flexbox
  125. getComputedStyle
  126. Intrinsic & Extrinsic Sizing
  127. letter-spacing CSS property
  128. Media Queries: interaction media features
  129. Media Queries: resolution feature
  130. prefers-color-scheme media query
  131. prefers-reduced-motion media query
  132. Rebeccapurple color
  133. rem (root em) units
  134. selector list argument of :not()
  135. SVG in CSS backgrounds
  136. system-ui value for font-family
  137. text-decoration styling
  138. text-emphasis styling
  139. TTF/OTF - TrueType and OpenType font support
  140. ui-serif, ui-sans-serif, ui-monospace and ui-rounded values for font-family
  141. Variable fonts
  142. Viewport units: vw, vh, vmin, vmax
  143. Window.devicePixelRatio
  144. #rrggbbaa hex color notation
  145. :default CSS pseudo-class
  146. :focus-visible CSS pseudo-class
  147. :focus-within CSS pseudo-class
  148. :indeterminate CSS pseudo-class
  149. :optional CSS pseudo-class
  150. background-position-x & background-position-y
  151. Crisp edges/pixelated images
  152. CSS @apply rule
  153. CSS Backdrop Filter
  154. CSS Canvas Drawings
  155. CSS Environment Variables env()
  156. CSS font-smooth
  157. CSS line-clamp
  158. CSS overscroll-behavior
  159. CSS pointer-events (for HTML)
  160. CSS Reflections
  161. CSS scrollbar styling
  162. CSS text-size-adjust
  163. CSS text-stroke and text-fill
  164. CSS zoom
  165. Explicit descendant combinator >>
  166. High-quality kerning pairs & ligatures
  167. Scoped CSS
  168. selector list argument of :nth-child and :nth-last-child CSS pseudo-classes
  169. All CSS features

HTML5

  1. accept attribute for file input
  2. Add to home screen (A2HS)
  3. async attribute for external scripts
  4. Attributes for form submission
  5. Audio element
  6. Audio Tracks
  7. Autofocus attribute
  8. Canvas (basic support)
  9. Canvas blend modes
  10. classList (DOMTokenList)
  11. Color input type
  12. contenteditable attribute (basic support)
  13. Custom Elements (V1)
  14. Custom protocol handling
  15. Datalist element
  16. dataset & data-* attributes
  17. Date and time input types
  18. defer attribute for external scripts
  19. Details & Summary elements
  20. Dialog element
  21. disabled attribute of the fieldset element
  22. Download attribute
  23. Drag and Drop
  24. Email, telephone & URL input types
  25. Form attribute
  26. Form validation
  27. getElementsByClassName
  28. Hashchange event
  29. hidden attribute
  30. HTML Imports
  31. HTML Media Capture
  32. HTML templates
  33. HTML5 form features
  34. HTML5 semantic elements
  35. indeterminate checkbox
  36. Inline SVG in HTML5
  37. input event
  38. input placeholder attribute
  39. inputmode attribute
  40. Lazy loading via attribute for images & iframes
  41. Link type "noreferrer"
  42. maxlength attribute for input and textarea elements
  43. meter element
  44. Minimum length attribute for input fields
  45. Multiple file selection
  46. naturalWidth & naturalHeight image properties
  47. Number input type
  48. OffscreenCanvas
  49. PageTransitionEvent
  50. Path2D
  51. Pattern attribute for input fields
  52. Picture element
  53. Ping attribute
  54. PNG favicons
  55. Printing Events
  56. progress element
  57. Range input type
  58. readonly attribute of input and textarea elements
  59. rel=noopener
  60. relList (DOMTokenList)
  61. Reversed attribute of ordered lists
  62. Ruby annotation
  63. sandbox attribute for iframes
  64. Search input type
  65. Selection controls for input & textarea
  66. Session history management
  67. Spellcheck attribute
  68. srcdoc attribute for iframes
  69. Srcset and sizes attributes
  70. Subresource Integrity
  71. SVG favicons
  72. tabindex global attribute
  73. Text API for Canvas
  74. Video element
  75. Video Tracks
  76. wbr (word break opportunity) element
  77. WebGL - 3D Canvas graphics
  78. WebGL 2.0
  79. Context menu item (menuitem element)
  80. Custom Elements (deprecated V0 spec)
  81. Offline web applications
  82. Portals
  83. seamless attribute for iframes
  84. All HTML5 features

Other

  1. "once" event listener option
  2. AAC audio file format
  3. autocomplete attribute: on & off values
  4. AV1 video format
  5. AVIF image format
  6. Brotli Accept-Encoding/Content-Encoding
  7. Built-in PDF viewer
  8. ChildNode.remove()
  9. Client Hints: DPR, Width, Viewport-Width
  10. CSS Paged Media (@page)
  11. Data URIs
  12. document.elementFromPoint()
  13. document.head
  14. document.scrollingElement
  15. DOM manipulation convenience methods
  16. DOMContentLoaded
  17. DOMMatrix
  18. Dynamic Adaptive Streaming over HTTP (MPEG-DASH)
  19. Element.closest()
  20. Element.insertAdjacentElement() & Element.insertAdjacentText()
  21. EventTarget.addEventListener()
  22. EventTarget.dispatchEvent
  23. FLAC audio format
  24. focusin & focusout events
  25. HEIF/ISO Base Media File Format
  26. HEVC/H.265 video format
  27. HTMLElement.innerText
  28. HTTP/2 protocol
  29. HTTP/3 protocol
  30. JPEG 2000 image format
  31. JPEG XR image format
  32. KeyboardEvent.code
  33. KeyboardEvent.getModifierState()
  34. KeyboardEvent.key
  35. KeyboardEvent.location
  36. MathML
  37. Media Fragments
  38. MP3 audio format
  39. MPEG-4/H.264 video format
  40. Mutation events
  41. Node.compareDocumentPosition()
  42. Node.textContent
  43. Ogg Vorbis audio format
  44. Ogg/Theora video format
  45. Opus
  46. Passive event listeners
  47. PNG alpha transparency
  48. querySelector/querySelectorAll
  49. Resource Hints: dns-prefetch
  50. Resource Hints: modulepreload
  51. Resource Hints: preconnect
  52. Resource Hints: prefetch
  53. Resource Hints: preload
  54. Resource Hints: prerender
  55. SDCH Accept-Encoding/Content-Encoding
  56. Shadow DOM (V1)
  57. Signed HTTP Exchanges (SXG)
  58. theme-color Meta Tag
  59. WAI-ARIA Accessibility features
  60. Wav audio format
  61. WebAssembly
  62. WebM video format
  63. WebVTT - Web Video Text Tracks
  64. WOFF - Web Open Font Format
  65. WOFF 2.0 - Web Open Font Format
  66. XHTML served as application/xhtml+xml
  67. Animated PNG (APNG)
  68. Document Policy
  69. EOT - Embedded OpenType fonts
  70. HTTP Live Streaming (HLS)
  71. KeyboardEvent.charCode
  72. KeyboardEvent.which
  73. Resource Hints: Lazyload
  74. Shadow DOM (deprecated V0 spec)
  75. SPDY protocol
  76. URL Scroll-To-Text Fragment
  77. WebP image format
  78. XHTML+SMIL animation
  79. All Other features

JS API

  1. AbortController & AbortSignal
  2. Accelerometer
  3. Ambient Light Sensor
  4. Auxclick
  5. Base64 encoding and decoding
  6. Basic console logging functions
  7. Battery Status API
  8. Beacon API
  9. Blob constructing
  10. Blob URLs
  11. BroadcastChannel
  12. Channel messaging
  13. console.time and console.timeEnd
  14. Constraint Validation API
  15. createImageBitmap
  16. Credential Management API
  17. Cross-document messaging
  18. Cross-Origin Resource Sharing
  19. crypto.getRandomValues()
  20. CSS.supports() API
  21. CustomEvent
  22. DeviceOrientation & DeviceMotion events
  23. Do Not Track API
  24. Document Object Model Range
  25. document.currentScript
  26. DOM Parsing and Serialization
  27. Element.getBoundingClientRect()
  28. Element.insertAdjacentHTML()
  29. Encrypted Media Extensions
  30. Feature Policy
  31. Fetch
  32. FIDO U2F API
  33. File API
  34. FileReader API
  35. FileReaderSync
  36. Full Screen API
  37. Gamepad API
  38. Geolocation
  39. getUserMedia/Stream API
  40. Gyroscope
  41. High Resolution Time API
  42. IndexedDB
  43. IndexedDB 2.0
  44. Input Method Editor API
  45. IntersectionObserver
  46. Magnetometer
  47. matches() DOM method
  48. matchMedia
  49. Media Capture from DOM Elements API
  50. Media Source Extensions
  51. MediaRecorder API
  52. Mutation Observer
  53. Navigation Timing API
  54. navigator.hardwareConcurrency
  55. Object RTC (ORTC) API for WebRTC
  56. Online/offline status
  57. Orientation Sensor
  58. Page Visibility
  59. Payment Request API
  60. Permissions Policy
  61. Pointer events
  62. Pointer Lock API
  63. Proximity API
  64. Push API
  65. requestAnimationFrame
  66. requestIdleCallback
  67. Resource Timing
  68. Screen Orientation
  69. Screen Wake Lock API
  70. Scroll methods on elements (scroll, scrollTo, scrollBy)
  71. scrollIntoView
  72. Selection API
  73. Server Timing
  74. Server-sent events
  75. Service Workers
  76. Shared Web Workers
  77. Streams
  78. Synchronous Clipboard API
  79. TextEncoder & TextDecoder
  80. Touch events
  81. URL API
  82. URLSearchParams
  83. User Timing API
  84. Vibration API
  85. Web Animations API
  86. Web Audio API
  87. Web Cryptography
  88. Web MIDI API
  89. Web Notifications
  90. Web Share API
  91. Web Sockets
  92. Web Storage - name/value pairs
  93. Web Workers
  94. WebRTC Peer-to-peer connections
  95. WebXR Device API
  96. XMLHttpRequest advanced features
  97. Background Sync API
  98. Directory selection from file input
  99. document.evaluate & XPath
  100. Document.execCommand()
  101. Efficient Script Yielding: setImmediate()
  102. Element.scrollIntoViewIfNeeded()
  103. Filesystem & FileWriter API
  104. IntersectionObserver V2
  105. Native Filesystem API
  106. Network Information API
  107. Permissions API
  108. Picture-in-Picture
  109. Resize Observer
  110. Speech Recognition API
  111. Speech Synthesis API
  112. Trusted Types for DOM manipulation
  113. Web Bluetooth
  114. Web NFC
  115. Web SQL Database
  116. WebGPU
  117. WebHID API
  118. WebUSB
  119. WebVR API
  120. All JS API features