Suggestion	Votes
1. HTTP content-encoding: zstd	45
2. Add HTTP 103 Early Hints	38
3. Add WebCodecs API	37
4. css/svg property dominant-baseline	35
5. Add CSS Color Module Level 5 (color-mix(), color-contrast(), Relative color)	34
6. Add support table for CSP 3.0 compliance	32
7. Suggestion: MediaRecorder.isTypeSupported supported types/codecs	29
8. Entries for href values including `tel:1234567` and `sms:1234567`	26
9. + WASM SIMD	25
10. Track support for newly added spec: Dimensions (width/height) in <source> tags	25
11. window.onerror - / - particularly mobile browser support	24
12. Add WebDriver	23
13. Can I use Reporting API	23
14. Priority hints API	23
15. text-wrap	23
16. Hyphenation Options	23
17. CSS3 module "Generated Content for Paged Media" and especially the target-counter function	22
18. Add ES7/2016 SIMD	21
19. Add customizable select element, currently `<selectmenu>`	20
20. WebExtensions (browser extensions)	19
21. I suggest adding statistics for Aural style sheets which contain CSS properties such as "speak....	19
22. New feature: CSS Typed Object Model (CSS Typed OM)	19
23. JavaScript: Tail Call Support information missing	19
24. XSLT Support table	19
25. Show Support for JSON Modules	19
26. TLS ECH (Encrypted Client Hello), formerly known as ESNI (Encrypted Server Name Indication)	19
27. Support constructible stylesheets / adoptedStyleSheets	18
28. Add CSS Grid Layout Module Level 3 (Masonry!)	17
29. border-corner-shape	16
30. device-cmyk css feature	16
31. Page Lifecycle API	16
32. Support Intrinsic Size Attribute	15
33. `content: leader('.');`	14
34. input-security	13
35. I suggest support for TransferableObject types (of which there are several)	13
36. Geo URI scheme	13
37. Check browser support for displaying MJPEG files. This is a motion JPEG file format that is supporte...	13
38. ElementInternals/form-associated custom element	13
39. Async iterators / for await of	12
40. SVGZ-specific support table since iOS < 4.2 doesn't support it, but does support SVG. Not su...	12
41. Color Fonts including SVG-in-OT fonts	12
42. Add WebRTC insertable streams	11
43. Add float: footnote to CSS3	11
44. New feature request: OCSP must-staple	11
45. webcl?	11
46. Soft hyphen: html entity &shy;	11
47. Add Webassembly Threads / Threaded Webassembly	11
48. CSS3 Speech Module Which browsers support it? See	10
49. caniuse : Constructable Stylesheet	10
50. Add Web Share Level 2	10
51. one-time-code	10
52. Add Report-To API (Intervention Reports)	10
53. Track Intl.Segmenter	10
54. CSS Box Alignment Module Level 3	10
55. queueMicrotask support	10
56. Support for SVG's "shape-rendering" CSS property.	10
57. @font-face descriptors to override font metrics	10
58. Add CSS animation timing function spring()	9
59. Add Web Share Target API	9
60. Cookies: max-age	9
61. Support CSS two-value display syntax	9
62. Add oklab() and oklch()	9
63. List support for the window.fetch keepalive option	9
64. Progressive JPEGs start to show on pages faster, from low quality and eventually getting their 100% ...	9
65. webM alpha transparency	9
66. Include `baseline-shift` CSS property	9
67. Quota Management API	9
68. Add caniuse data for Contact Picker API	9
69. Add supported elliptical curves (HTTPS/TLS)	8
70. Badging API	8
71. SVG viewport-fill-opacity property support	8
72. SVG viewport-fill property support	8
73. Add `accent-color` property (CSS UI 4)	8
74. WebGL extensions	8
75. HTTP2 Server Push	8
76. HTMLVideoElement.requestVideoFrameCallback()	8
77. Add CSS property `caret-shape` and shorthand `caret`	8
78. Support for the frame-ancestors directive	7
79. Please add "isInputPending()"	7
80. Tiff image format	7
81. input[autocomplete] (values besides on/off)	7
82. Add `WebOTP` to list of apis	7
83. Feature: Origin-bound one-time codes delivered via SMS	7
84. HTML Modules	7
85. This regards adding support for the navigator.userAgentData	7
86. Secure Cookie flag	7
87. Alt-Svc header browser support info: consider adding	7
88. autocorrect for input fileds	7
89. Add SVG `use` with external reference	7
90. RFC7692 Compression Extensions for WebSocket	7
91. Add ShadowRealm API	7
92. User-Agent Client Hints (UA-CH)	7
93. Flag storage that is not available under private mode	6
94. Add Web Share Target API Level 2	6
95. WebCrypto Key Discovery	6
96. Accelerated Shape Detection in Images	6
97. CSS 3 property: text-autospace and text-spacing	6
98. Add CSS module script/CSS modules	6
99. Observable	6
100. MediaStream Image Capture	6
101. Geofencing API	6
102. Module Worker support	6
103. Add `enterkeyhint` attribute ("Enter Key Hint")	6
104. Cannot see |ImageCapture| entry in the web interface.	6
105. CSS tag {content: url()}	6
106. Add autocorrect, autocapitalize, autocomplete attributes	6
107. Page-margin boxes (@top-center, etc)	6
108. New feature request: x25519 Key Exchange	6
109. Add CSS Values and Units Module Level 4 Mathematical Expressions	6
110. Add support for Trust Tokens API	6
111. Add 'require-sri-for' CSP Directive	6
112. Add `multipart/x-mixed-replace`	6
113. new CSS trigonometry functions	5
114. Add Eyedropper API to caniuse	5
115. USDZ file format	5
116. Add "outline follows border-radius"	5
117. roundRect	5
118. navigator.isProtocolHandlerRegistered and .unregisterProtocolHandler	5
119. [WebCryptoAPI] randomUUID	5
120. External import maps	5
121. Support individual CSP rules	5
122. Add ECC certificates	5
123. Audio codec - xHE-AAC / USAC	5
124. Embedded color profiles in JPEG images.	5
125. Please track the various HTTP Set-Cookie options supported by browsers	5
126. mediagroup content attribute, MediaController object, VideoTrackList, AudioTrackList objects	5
127. -ms-overflow-style	5
128. Add the Quite OK Image Format (QOI) …maybe eventually	5
129. Adding Khronos gITF 2.0 for 3D models	5
130. Add System Colors item	5
131. HTTP Strict Transport Security Preload	5
132. Add Versatile Video Coding (VVC) … somewhen	5
133. Add info about css user-modify and -webkit-user-modify:read-write-plaintext-only	5
134. Bundled HTTP Exchanges	5
135. Feature: A Well-Known URL for Changing Passwords	5
136. Add font-palette-values	5
137. Add CSS Custom Highlight API	5
138. audio / video autoplay attribute and play function	5
139. Add support tables for document.documentElement.clientWidth	5
140. Window Placement API	4
141. Add raw sockets API	4
142. Support the W3 Web Annotation standard (W3C Recommendation)	4
143. ::-webkit-file-upload-button	4
144. CSS Round Display	4
145. New top level domains (TLD)	4
146. allowtransparency	4
147. CSS Shaders -	4
148. [CSS Level 4 pseudo-class] :user-error	4
149. CSS image() functional notation (e.g. for background-images etc). See	4
150. Add the `<model>` element	4
151. Web locks	4
152. Add supports() queries on @import	4
153. Payment Handler API	4
154. Cache-Control	4
155. Support for Digital Goods API	4
156. TCP Fast-Open. Now that Linux kernels enable this by default (and web servers likely won't be ...	4
157. Screen Capture	4
158. Support aria-hidden html property	4
159. For printing support for the size:landscape option to tell the browser what page orientation we want...	4
160. Add Cookie Store API	4
161. Input Events Level 1 and 2	4
162. Add the `:modal` pseudo-class	4
163. add Accessibility Object Model	4
164. Global Privacy Control (GPC) "Sec-GPC" HTTP header	4
165. The !important css thing. It's very !important ;).	4
166. Arithmetic coded JPEG support	4
167. Support for MHTML	4
168. JS Self-Profiling API	4
169. getEventListeners not listed	3
170. Add Media Session API Coverage Information	3
171. place-items shorthand for justify and align	3
172. CSS multicol data is mixed with fragmentation	3
173. Add <data> element	3
174. add window-inactive pseudo-class	3
175. Add information for the webcal and webcals protocols for subscribing to iCalendars	3
176. ECMAscript - static properties	3
177. Accessibility of in-browser PDF Viewer	3
178. Support SVG width/height = auto	3
179. http://www.w3.org/TR/web-alarms/	3
180. Add meta "format-detection"	3
181. ActiveX	3
182. New browser feature: rest/spread in object literals	3
183. CanIUse OpenSearch	3
184. Can I Use m4a?	3
185. Add "fetchpriority"	3
186. Add Intl.DisplayNames	3
187. The "auto" value for the dir attribute, added in HTML5 to ease inserting text of unknown d...	3
188. Add support for requestSubmit	3
189. Add `dynamic-range` media query	3
190. Public class properties	3
191. Private Click Measurement (PCM)	3
192. Tracking various WebAuthn features	3
193. Add support for DNS RRs, like HTTPS and SVCB	3
194. documentMode	3
195. Add support for addHitRegion	3
196. SVG sprites with <symbol> and <use>	3
197. getTotalLength()	3
198. display: table-caption?	3
199. <semantics> element in MathML is not found in caniuse.com	2
200. Show ANSI escape code for console.log.	2
201. Add Geolocation Sensor	2
202. Add Integrated Windows Authentication	2
203. Wildcard "*" support for Access-Control-Allow-Headers/Methods	2
204. Add Sanitizer API	2
205. SSML	2
206. Add information on context-stroke and context-fill	2
207. webkit-calendar-picker-indicator	2
208. EventTarget Constructor	2
209. support destructuring assignment as separate es feature	2
210. dns.resolve	2
211. Loading Signed Exchanges	2
212. Support KV Storage build-in module	2
213. Graphite font support	2
214. rel="ar" support	2
215. Storage Access API	2
216. WebXR Hand Input Module - Level 1	2
217. track support for the media query feature -ms-high-contrast	2
218. Spatial Navigation support	2
219. MediaDevices.selectAudioOutput	2
220. Missing feature: Clipboard API supported mimetypes	2
221. add "unicode property escapes"	2
222. justify-content: space-around	2
223. Please add ES3 support	2
224. Add PNG cursor	2
225. Add TPG image file format	2
226. CSS touch-action level 2 values	2
227. Add "page based counters"	2
228. Content-Security-Policy: script-nonce	2
229. UTF-8 Dingbats	2
230. Directional focus navigation: the nav-up, nav-right, nav-down, nav-left properties	2
231. SharedMemory/Atomics	2
232. A new page for Grid track animation should be added	2
233. Add 'animated GIF as favicon'?	2
234. Request: nav-up, nav-down, nav-left, nav-right css3 properties	2
235. Container Queries should be broken out into three pages	2
236. Input type=email with "multiple" attribute	2
237. Add Wide Color Gamut in 2D Canvas	2
238. Add "Window Controls Overlay"	2
239. Support of sms: and mms: in mobile browsers is not clear	2
240. console.assert(boolean_expression)	2
241. "GeometryUtils" - part of the CSSOM. Provides much better position information than existi...	2
242. filename*=UTF-8''...	2
243. Add other values of `user-select` property	2
244. webp2 support	2
245. add csp lv2 violation event	2
246. HTTP Trailers	2
247. Animating SVG paths using CSS	2
248. Add the HTML focusgroup attribute	2
249. onerror event on iframe	2
250. Add Local Font Access API	2
251. Can I use X3D?	2
252. Add gRPC support	2
253. File Handling API	2
254. Basic Authentication: AuthName directive	2
255. Add chrome.webrequests	2
256. Web bundles	2
257. Add Scoped Styles aka. CSS Scoping	2
258. x-webkit-speech	2
259. Touch Icons (apple-touch-icon)	2
260. Add browser support for toggle()	2
261. SameParty cookie attribute	2
262. Bitmap images inside SVG files. Some browsers that support SVG, will not show embedded bitmap image...	2
263. getFilesAndDirectories	2
264. srcset/sizes attribute / picture element support in SVG	2
265. What about showing support for various link attributes, like "subresource" or "dns-pr...	2
266. setTimeout and setInterval callback parameters	2
267. Device-Memory Client Hint & navigator.deviceMemory JS API	2
268. stroke-linejoin support	2
269. CSS page property (for printing)	2
270. HTTP immutable responses	2
271. Tooltip display on focus	2
272. Support for CSS3 background-repeat-x and background-repeat-y properties	2
273. add captureVisibleTab	2
274. SVG image auto height	2
275. add iframe.csp	2
276. Load event support on link nodes to show when a stylesheet is finished loading. See for a discussio...	2
277. Track adoption of DOMFrameContentLoaded event	2
278. String.prototype.split() with a regex with grouping ( parentheses ).	2
279. css animation on “content:” - works on chrome, doesn't work on Safari and Firefox	1
280. Add `blocking=render`	1
281. Add IndexedDB 3.0	1
282. sec-ch-prefers headers	1
283. iframe disallowdocumentaccess property	1
284. import reflection for WASM	1
285. Add CSS Toggles …maybe eventually	1
286. Sec-Ch-wow64	1
287. Add `font-variant-emoji`	1
288. Adding contain-intrinsic-size (suggestion)	1
289. Streams API: transferable streams	1
290. Support information for horizontal-viewport-segments and vertical-viewport-segments	1
291. Add Fetch upload streaming	1
292. Add Capture Handle	1
293. Add the Pop Up API aka. the `popup` attribute plus more	1
294. Add Web MIDI 2.0 …maybe eventually	1
295. text-space-collapse	1
296. Add `::target-text` (from CSS Pseudo-Elements Module Level 4)	1
297. Add CSS Scroll Snap Module Level 2	1
298. Add `target="_new"`	1
299. Add "Scheduled Task API"	1
300. Add VisualViewport.segments support data	1
301. Metadata name: MobileOptimized	1
302. Add `Notification.prototype​.showTrigger️`	1
303. Add: "color" and "background-color" CSS on <option> elements	1
304. nested calc() and var()	1
305. FLoC support	1
306. voice-* properties aren't listed	1
307. Please add more detailed WebRTC features	1
308. add RTSP and RTSP 2.0 (Real Time Streaming Protocol)	1
309. Add `::-webkit-details-marker`	1
310. stroke-linecap support	1
311. Add URL Protocol Handler Registration for PWAs	1
312. feature request: video/MP2T	1
313. Can you please add the Stack trace API that exists in V8	1
314. Show which browsers have a native CSV viewer	1
315. Add entry for DTLS 1.3	1
316. requestPostAnimationFrame browser support?	1
317. missing HTTP TRACE method	1
318. E4X: ECMAScript for XML	1
319. Add "specifying a color profile: the `@color-profile` at-rule"	1
320. Add `media` attribute for `<meta>` element (for `<meta name="theme-color">`)	1
321. bidi algorithm (for right-to-left Unicode characters)	1
322. Add Container Units aka. Container Relative Lengths	1
323. Add optional type syntax for JavaScript …maybe eventually	1
324. device-pixel-content-box for ResizeObserver	1
325. performance.measureMemory()	1
326. TLS Encrypted Client Hello (ECH)	1
327. Support HTJ2K	1
328. `from-image` as initial value of `image-orientation`	1
329. auto Picture-in-Picture	1
330. MPNG	1
331. Metadata name: HandheldFriendly	1
332. Support for hrefTranslate	1
333. Add server-timing as a trailer	1
334. Add MathML Core	1
335. Add IPFS (Interplanetary File System) protocol to Caniuse	1
336. No information about the `unselectable` HTML attribute.	1
337. Add Date.prototype.toTemporalInstant()	1
338. Add Web Neural Network (WebNN)	1
339. Add support information for font metric override descriptors	1
340. Add CMYK Color Space	1
341. Add Notification Triggers	1
342. Add compatibility data for QuickTime video format	1
343. Can I use windowtext.	1
344. Suggestion: support for margin-collapse?	1
345. CMAF	1
346. attachEvent event handler missing from CanIUse	1
347. add CSS Extensions meant for renaming	1
348. Add a footnote regarding HTMLAudioElement	1
349. Support info for the <track> element	1
350. Drag and Drop API - move constraints	1
351. Drag and Drop API - ghost image with customizable opacity	1
352. Audio Output Devices API: wd	1
353. DeviceOrientation and DeviceMotion events on insecure origins	1
354. audio / video .canPlayType(MIMEtype)	1
355. Add Range.getBoundingClientRect browser support table	1
356. Add support for mediacapture-output API's sinkID	1
357. document type	1
358. Add HTTP_ORIGIN feature	1
359. Add box-suppress	1
360. string-set	1
361. Add CSS4 Grid structural selectors	1
362. Internationalized Domain Name	1
363. column combination	1
364. SHA2 certificates	1
365. event.path	1
366. Add "Named function expressions"	1
367. Open search autodiscovery	1
368. add mouse event positions event.offsetX and event.offsetY	1
369. reflected-xss missing	1
370. Add XSL to caniuse	1
371. Add support for CSS3 move-to property	1
372. Missing `StorageQuota` support	1
373. aria-labelledby	1
374. SHA1 certificates	1
375. Add support for HTTP header X-Permitted-Cross-Domain-Policies	1
376. request support for 'accept-charset'	1
377. browserconfig.xml support info	1
378. add micropub	1
379. create @Media Types	1
380. line-height support and the differences in rendering between webkit&trident and other engines.	1
381. I suggest adding information about support for alternate HTTP methods such as PUT and PATCH.	1
382. Browser support for RTP streams?	1
383. Textarea wrap attribute (off, soft, hard, virtual, physical)	1
384. Web intents/Web Activities	1
385. Support for XPath 2.0 (interesting for a lot of new functions, like base-uri(), matches() etc.)	1
386. <meta name="apple-mobile-web-app-capable" content="yes" />	1
387. accesskey attribute on non-focusable elements (should cause a click element to fire	1
388. MediaStream Recording (	1
389. The hanging-punctuation property: Currently unsupported by any browser, but it would be nice to ...	1
390. image-resolution. I've seen this as a good alternative for retina images as opposed to backgro...	1
391. script tag onerror attribute	1
392. Suggestion for caniuse.com: Which browsers.versions support multiple tbody elements in a single table?	1
393. Input type=range with "multiple" attribute	1
394. Edge and IE don't support IndexedDB in web workers	1
395. longdesc attribute support	1
396. CSS Inline Layout	1
397. IETF RFCs	1
398. Feature request: Token Binding Protocol	1
399. add onstorage	1
400. background-composite	1
401. Add WebKit Tap Highlight Color (-webkit-tap-highlight-color)?	1
402. Add windows-theme media query selector	1
403. window.localMediaStream is not listed	1
404. ie behavior	1
405. The xml:space attribute	1
406. show support for namespacing; for example <svg: namespace	1
407. Add Object.prototype.watch method	1
408. Please add support for getTimezoneOffset()	1
409. Add support for the HTTP header X-Download-Options	1
410. support data suggestion: DOM event constructors ?	1
411. Add support for svg fill-rule	1
412. The event handler window.onscroll is missing	1
413. date.toLocaleString support tracking plz?	1
414. https mixed mode	1
415. Add page for relative path in HTTP Location	1
416. OfflineAudioContext	1
417. DownloadURL	1
418. Use of es6 import statements in workers	1
419. CSS3 new text-transform keywords	1
420. step property of input field with type datetime-local and time	1
421. please add the onsearch event	1
422. supported-color-schemes & prefers-color-scheme	1
423. <object>.contentWindow Support	1
424. Refresh	1
425. How to show support for font-variation-settings within @font-face?	1
426. baseline-middle	1
427. online/offline can also be used as events and are not covered by caniuse.com (only boolean property is covered)	1
428. Please add JavaScript string functions trimStart, trimEnd, trimRight, trimLeft	1
429. Support for calc() in polygon and other shapes	1
430. Request: IPv6 proxy functions (myIpAddressEx and friends)	1
431. Clean up css-touch-action	1
432. Add desynchronized (low latency canvas contexts)	1
433. @top-left @bottom-center ? can you test for compatibility	1
434. Add Support for MPEG-4 Part 2 SP/ASP	1
435. grid-row-gap and grid-column-gap	1
436. Add the Javascript double asterisk power operator (**) to the list of supported features	1
437. x-webkit-airplay	1
438. What is the browser support for the newly proposed "page-orientation" property?	1
439. Add layout-instability support	1
440. Information about WavPack audio format	1
441. InsertKey Behaviour Overwrite/Normal Mode	1
442. Report Retry-After header support	1
443. Suggested addition: navigator.cpuClass	1
444. [Suggestion] display: fullscreen	1
445. Javascript pseudoprotocol	1
446. Add High Resolution Time Level 3	1
447. Add: Task Scheduler API Specification	1
448. Add css-timing	1
449. aria-current	1
450. add aria-required to caniuse, if not already there	1
451. Add app-region?	1
452. URLSearchParams.prototype.sort	1
453. SVG symbols in CSS	1
454. Need full 3gp browser compatibility chart.Does it chrome browser supports 3gp format	1
455. Add "Controlling Font Display Per Font-Family via @font-feature-values"	1
456. Video media in image contexts	1
457. Please add support for supported x509 extensions for ʜᴛᴛᴘꜱ certificates	1
458. Chained selectors	1
459. Browser support for displaying the unicode block "Combining Diacritical Marks for Symbols"	1
460. Support for RegExp Named Capture Groups	1
461. Support for Unicode and spaces in URL	1
462. Support data for Unicode flag on HTML pattern attribute	1
463. HTTP Content-encoding: LZFSE	1
464. IPv6 support in web browsers	1
465. add ime-mode	1
466. Add: Tracking Preference Expression APIs	1
467. Missing computed property names	1
468. Character-based alignment in a table column using text-align	1
469. [Feature Policy: sub-feature] Sandbox features	1
470. window.watchMedia()	1
471. Add compatibility for FormData	1
472. Add H2 ORIGIN frame support	1
473. Add a matrix entyre for opentype-with-cff2	1
474. Support for Service Worker Life Cycle Events	1
475. Add `WebSocketStream` API	1