BCD Watch

BCD Changes Report

Summary of BCD changes from through 🔗

Browser Support Changes: +13, -0

Support increases (13)

API

  1. api ➞ HTMLElement ➞ popover ➞ hint Spec link
    Added to Firefox  ➞  2 of 3 engines
  2. api ➞ HTMLInputElement ➞ showPicker ➞ datalist_input
    Added to Firefox  ➞  3 of 3 engines

HTML

  1. html ➞ global_attributes ➞ popover ➞ hint Spec link
    Added to Firefox  ➞  2 of 3 engines

WEBDRIVER

  1. webdriver ➞ bidi ➞ emulation ➞ setNetworkConditions Spec link
    Added to Firefox  ➞  2 of 3 engines
  2. webdriver ➞ bidi ➞ emulation ➞ setNetworkConditions ➞ contexts_parameter Spec link
    Added to Firefox  ➞  2 of 3 engines
  3. webdriver ➞ bidi ➞ emulation ➞ setNetworkConditions ➞ networkConditions_parameter Spec link
    Added to Firefox  ➞  2 of 3 engines
  4. webdriver ➞ bidi ➞ emulation ➞ setNetworkConditions ➞ networkConditions_parameter ➞ offline Spec link
    Added to Firefox  ➞  2 of 3 engines
  5. webdriver ➞ bidi ➞ emulation ➞ setNetworkConditions ➞ userContexts_parameter Spec link
    Added to Firefox  ➞  2 of 3 engines

WEBEXTENSIONS

  1. webextensions ➞ api ➞ tabs ➞ SPLIT_VIEW_ID_NONE
    Added to Firefox  ➞  2 of 3 engines
  2. webextensions ➞ api ➞ tabs ➞ Tab ➞ splitViewId
    Added to Firefox  ➞  2 of 3 engines
  3. webextensions ➞ api ➞ tabs ➞ onUpdated ➞ changeInfo ➞ splitViewId
    Added to Firefox  ➞  2 of 3 engines
  4. webextensions ➞ api ➞ tabs ➞ onUpdated ➞ filter ➞ properties ➞ splitViewId
    Added to Firefox  ➞  1 of 3 engines
  5. webextensions ➞ api ➞ tabs ➞ query ➞ queryInfo ➞ splitViewId
    Added to Firefox  ➞  2 of 3 engines

BCD Metadata Changes: 54

Show all 54 changes

Note: The following represent changes to BCD metadata keys in the reported time period. Keys are not implementations, and they don't represent commitments toward implementation, etc. A new key occurring is perhaps a signal that some implementer was serious enough to add the key. Many of the features that are 'removed' are usually just 'moved' or 'renamed', but we don't have great ways to highlight that.

Backfilled entries (25)

The entries in this section saw support information change since the report on Friday, 27 February 2026, but all the supported browser versions given were more than a couple of months old. Typically, these are cases of support information being updated long after the support actually landed in a browser, but nobody ever updated the BCD entry.

API

  1. api ➞ HTMLSelectedContentElement
    Backfilled for Safari  ➞  2 of 3 engines
  2. api ➞ CSSFontFaceRule ➞ style ➞ type_CSSFontFaceDescriptors
    Backfilled for Safari  ➞  1 of 3 engines
  3. api ➞ Navigator ➞ preferences Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  4. api ➞ PreferenceManager Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  5. api ➞ PreferenceManager ➞ colorScheme Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  6. api ➞ PreferenceManager ➞ contrast Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  7. api ➞ PreferenceManager ➞ reducedData Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  8. api ➞ PreferenceManager ➞ reducedMotion Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  9. api ➞ PreferenceManager ➞ reducedTransparency Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  10. api ➞ PreferenceObject Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  11. api ➞ PreferenceObject ➞ change_event Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  12. api ➞ PreferenceObject ➞ clearOverride Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  13. api ➞ PreferenceObject ➞ override Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  14. api ➞ PreferenceObject ➞ requestOverride Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  15. api ➞ PreferenceObject ➞ validValues Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  16. api ➞ PreferenceObject ➞ value Spec link
    Backfilled for Chrome  ➞  1 of 3 engines
  17. api ➞ WGSLLanguageFeatures ➞ extension_uniform_buffer_standard_layout Spec link
    Backfilled for Chrome  ➞  1 of 3 engines

CSS

  1. css ➞ properties ➞ appearance ➞ base-select Spec link
    Backfilled for Safari  ➞  2 of 3 engines
  2. css ➞ selectors ➞ open
    Backfilled for Safari  ➞  2 of 3 engines
  3. css ➞ selectors ➞ picker
    Backfilled for Safari  ➞  2 of 3 engines
  4. css ➞ selectors ➞ picker-icon
    Backfilled for Safari  ➞  2 of 3 engines
  5. css ➞ properties ➞ appearance ➞ base-select ➞ listbox
    Backfilled for Chrome  ➞  1 of 3 engines
  6. css ➞ properties ➞ appearance ➞ base-select ➞ single_dropdown
    Backfilled for Chrome  ➞  2 of 3 engines

JAVASCRIPT

  1. javascript ➞ builtins ➞ JSON ➞ isRawJSON
    Backfilled for Safari  ➞  3 of 3 engines
  2. javascript ➞ builtins ➞ JSON ➞ rawJSON
    Backfilled for Safari  ➞  3 of 3 engines

New entries (29)

The entries in this section were not found in BCD on Friday, 27 February 2026, but are now present. These usually do not have any support information attached to them, and often have no corresponding MDN page. Sometimes, entries that appear here also appear in the next section (“Removed BCD entries”) because of a Working Group deciding on a rename.

API

  1. api ➞ CSSFontFaceRule ➞ style ➞ type_CSSFontFaceDescriptors
  2. api ➞ Navigator ➞ preferences
  3. api ➞ PreferenceManager
  4. api ➞ PreferenceManager ➞ colorScheme
  5. api ➞ PreferenceManager ➞ contrast
  6. api ➞ PreferenceManager ➞ reducedData
  7. api ➞ PreferenceManager ➞ reducedMotion
  8. api ➞ PreferenceManager ➞ reducedTransparency
  9. api ➞ PreferenceObject
  10. api ➞ PreferenceObject ➞ change_event
  11. api ➞ PreferenceObject ➞ clearOverride
  12. api ➞ PreferenceObject ➞ override
  13. api ➞ PreferenceObject ➞ requestOverride
  14. api ➞ PreferenceObject ➞ validValues
  15. api ➞ PreferenceObject ➞ value
  16. api ➞ WGSLLanguageFeatures ➞ extension_uniform_buffer_standard_layout

CSS

  1. css ➞ properties ➞ appearance ➞ base-select ➞ listbox
  2. css ➞ properties ➞ appearance ➞ base-select ➞ multiple_dropdown
  3. css ➞ properties ➞ appearance ➞ base-select ➞ single_dropdown

HTTP

  1. http ➞ headers ➞ Sec-Secure-Session-Id
  2. http ➞ headers ➞ Secure-Session-Challenge
  3. http ➞ headers ➞ Secure-Session-Registration
  4. http ➞ headers ➞ Secure-Session-Response
  5. http ➞ headers ➞ Secure-Session-Skipped

WEBEXTENSIONS

  1. webextensions ➞ api ➞ tabs ➞ SPLIT_VIEW_ID_NONE
  2. webextensions ➞ api ➞ tabs ➞ Tab ➞ splitViewId
  3. webextensions ➞ api ➞ tabs ➞ onUpdated ➞ changeInfo ➞ splitViewId
  4. webextensions ➞ api ➞ tabs ➞ onUpdated ➞ filter ➞ properties ➞ splitViewId
  5. webextensions ➞ api ➞ tabs ➞ query ➞ queryInfo ➞ splitViewId

Removed entries (0)

No features were removed from bcd in this time period