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 content-visibility
  33. CSS Counter Styles
  34. CSS Counters
  35. CSS Cross-Fade Function
  36. CSS currentColor value
  37. CSS Device Adaptation
  38. CSS display: contents
  39. CSS element() function
  40. CSS Exclusions Level 1
  41. CSS Feature Queries
  42. CSS Filter Effects
  43. CSS filter() function
  44. CSS first-line pseudo-element
  45. CSS Flexible Box Layout Module
  46. CSS Font Loading
  47. CSS font-feature-settings
  48. CSS font-rendering controls
  49. CSS font-size-adjust
  50. CSS font-stretch
  51. CSS font-variant-alternates
  52. CSS font-variant-numeric
  53. CSS Generated content for pseudo-elements
  54. CSS grab & grabbing cursors
  55. CSS Gradients
  56. CSS Grid Layout (level 1)
  57. CSS hanging-punctuation
  58. CSS Hyphenation
  59. CSS image-set
  60. CSS Initial Letter
  61. CSS initial value
  62. CSS inline-block
  63. CSS justify-content: space-evenly
  64. CSS line-clamp
  65. CSS Logical Properties
  66. CSS Masks
  67. CSS math functions min(), max() and clamp()
  68. CSS min/max-width/height
  69. CSS Motion Path
  70. CSS namespaces
  71. CSS outline properties
  72. CSS overflow property
  73. CSS overflow-anchor (Scroll Anchoring)
  74. CSS page-break properties
  75. CSS Paint API
  76. CSS position:fixed
  77. CSS position:sticky
  78. CSS Regions
  79. CSS Repeating Gradients
  80. CSS resize property
  81. CSS revert value
  82. CSS Scroll Snap
  83. CSS Shapes Level 1
  84. CSS Subgrid
  85. CSS Table display
  86. CSS text-indent
  87. CSS text-justify
  88. CSS text-orientation
  89. CSS touch-action property
  90. CSS unset value
  91. CSS user-select: none
  92. CSS Variables (Custom Properties)
  93. CSS widows & orphans
  94. CSS will-change property
  95. CSS writing-mode property
  96. CSS3 2D Transforms
  97. CSS3 3D Transforms
  98. CSS3 attr() function for all properties
  99. CSS3 Background-image options
  100. CSS3 Border images
  101. CSS3 Border-radius (rounded corners)
  102. CSS3 Box-shadow
  103. CSS3 Box-sizing
  104. CSS3 Colors
  105. CSS3 Cursors (original values)
  106. CSS3 Cursors: zoom-in & zoom-out
  107. CSS3 font-kerning
  108. CSS3 image-orientation
  109. CSS3 Media Queries
  110. CSS3 Multiple backgrounds
  111. CSS3 Multiple column layout
  112. CSS3 object-fit/object-position
  113. CSS3 Opacity
  114. CSS3 Overflow-wrap
  115. CSS3 selectors
  116. CSS3 tab-size
  117. CSS3 text-align-last
  118. CSS3 Text-overflow
  119. CSS3 Text-shadow
  120. CSS3 Transitions
  121. CSS3 word-break
  122. CSSOM Scroll-behavior
  123. display: flow-root
  124. display: run-in
  125. Font unicode-range subsetting
  126. gap property for Flexbox
  127. getComputedStyle
  128. Intrinsic & Extrinsic Sizing
  129. letter-spacing CSS property
  130. Media Queries: interaction media features
  131. Media Queries: resolution feature
  132. prefers-color-scheme media query
  133. prefers-reduced-motion media query
  134. Rebeccapurple color
  135. rem (root em) units
  136. selector list argument of :not()
  137. SVG in CSS backgrounds
  138. system-ui value for font-family
  139. text-decoration styling
  140. text-emphasis styling
  141. TTF/OTF - TrueType and OpenType font support
  142. ui-serif, ui-sans-serif, ui-monospace and ui-rounded values for font-family
  143. Variable fonts
  144. Viewport units: vw, vh, vmin, vmax
  145. Window.devicePixelRatio
  146. #rrggbbaa hex color notation
  147. :default CSS pseudo-class
  148. :focus-visible CSS pseudo-class
  149. :focus-within CSS pseudo-class
  150. :indeterminate CSS pseudo-class
  151. :optional CSS pseudo-class
  152. background-position-x & background-position-y
  153. Crisp edges/pixelated images
  154. CSS @apply rule
  155. CSS @scroll-timeline
  156. CSS Backdrop Filter
  157. CSS Canvas Drawings
  158. CSS Environment Variables env()
  159. CSS font-smooth
  160. CSS overscroll-behavior
  161. CSS pointer-events (for HTML)
  162. CSS Reflections
  163. CSS scrollbar styling
  164. CSS text-size-adjust
  165. CSS text-stroke and text-fill
  166. CSS zoom
  167. Explicit descendant combinator >>
  168. High-quality kerning pairs & ligatures
  169. Scoped CSS
  170. selector list argument of :nth-child and :nth-last-child CSS pseudo-classes
  171. 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. Asynchronous Clipboard API
  5. Auxclick
  6. Base64 encoding and decoding
  7. Basic console logging functions
  8. Battery Status API
  9. Beacon API
  10. Blob constructing
  11. Blob URLs
  12. BroadcastChannel
  13. Channel messaging
  14. console.time and console.timeEnd
  15. Constraint Validation API
  16. createImageBitmap
  17. Credential Management API
  18. Cross-document messaging
  19. Cross-Origin Resource Sharing
  20. crypto.getRandomValues()
  21. CSS.supports() API
  22. CustomEvent
  23. DeviceOrientation & DeviceMotion events
  24. Do Not Track API
  25. Document Object Model Range
  26. document.currentScript
  27. DOM Parsing and Serialization
  28. Element.getBoundingClientRect()
  29. Element.insertAdjacentHTML()
  30. Encrypted Media Extensions
  31. Feature Policy
  32. Fetch
  33. FIDO U2F API
  34. File API
  35. FileReader API
  36. FileReaderSync
  37. Full Screen API
  38. Gamepad API
  39. Geolocation
  40. getUserMedia/Stream API
  41. Gyroscope
  42. High Resolution Time API
  43. IndexedDB
  44. IndexedDB 2.0
  45. Input Method Editor API
  46. IntersectionObserver
  47. Magnetometer
  48. matches() DOM method
  49. matchMedia
  50. Media Capture from DOM Elements API
  51. Media Source Extensions
  52. MediaRecorder API
  53. Mutation Observer
  54. Navigation Timing API
  55. navigator.hardwareConcurrency
  56. Object RTC (ORTC) API for WebRTC
  57. Online/offline status
  58. Orientation Sensor
  59. Page Visibility
  60. Payment Request API
  61. Permissions Policy
  62. Pointer events
  63. Pointer Lock API
  64. Proximity API
  65. Push API
  66. requestAnimationFrame
  67. requestIdleCallback
  68. Resource Timing
  69. Screen Orientation
  70. Screen Wake Lock API
  71. Scroll methods on elements (scroll, scrollTo, scrollBy)
  72. scrollIntoView
  73. Selection API
  74. Server Timing
  75. Server-sent events
  76. Service Workers
  77. Shared Web Workers
  78. Streams
  79. Synchronous Clipboard API
  80. TextEncoder & TextDecoder
  81. Touch events
  82. URL API
  83. URLSearchParams
  84. User Timing API
  85. Vibration API
  86. Web Animations API
  87. Web Audio API
  88. Web Cryptography
  89. Web MIDI API
  90. Web Notifications
  91. Web Share API
  92. Web Sockets
  93. Web Storage - name/value pairs
  94. Web Workers
  95. WebRTC Peer-to-peer connections
  96. WebXR Device API
  97. XMLHttpRequest advanced features
  98. Background Sync API
  99. Directory selection from file input
  100. document.evaluate & XPath
  101. Document.execCommand()
  102. Efficient Script Yielding: setImmediate()
  103. Element.scrollIntoViewIfNeeded()
  104. File System Access API
  105. Filesystem & FileWriter API
  106. IntersectionObserver V2
  107. Network Information API
  108. Permissions API
  109. Picture-in-Picture
  110. Resize Observer
  111. Speech Recognition API
  112. Speech Synthesis API
  113. Trusted Types for DOM manipulation
  114. Web Bluetooth
  115. Web NFC
  116. Web SQL Database
  117. WebGPU
  118. WebHID API
  119. WebUSB
  120. WebVR API
  121. All JS API features