Now Stable

"New on the Web": For a given set of browsers, what APIs became stable and when, ordered reverse chronologically.

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Browsers
Features

Stable APIs

Below is a list of features that are in Firefox and Safari, ordered reverse chronologically by when they became stable (i.e, available in the last browser).

2025/12

API First Browser Date Last Browser Date Days Notes
webassembly.api.Memory.toFixedLengthBuffer 📋Firefox11/11/2025 Safari12/12/202531
webassembly.api.Memory.toResizableBuffer 📋Firefox11/11/2025 Safari12/12/202531
webassembly.jsStringBuiltins 📋Firefox1/7/2025 Safari12/12/2025339

2025/3

API First Browser Date Last Browser Date Days Notes
webassembly.api.JSTag_static 📋Firefox10/1/2024 Safari3/31/2025181
webassembly.exceptionsFinal 📋Firefox10/1/2024 Safari3/31/2025181

2024/12

API First Browser Date Last Browser Date Days Notes
webassembly.garbage-collection 📋Firefox11/21/2023 Safari12/11/2024386
webassembly.tail-calls 📋Firefox12/19/2023 Safari12/11/2024358

2024/9

API First Browser Date Last Browser Date Days Notes
webassembly.typedFunctionReferences 📋Firefox11/21/2023 Safari9/16/2024300

2024/3

API First Browser Date Last Browser Date Days Notes
webassembly.extended-constant-expressions 📋Firefox4/11/2023 Safari3/5/2024329

2023/3

API First Browser Date Last Browser Date Days Notes
webassembly.fixed-width-SIMD 📋Firefox6/1/2021 Safari3/27/2023664

2022/5

API First Browser Date Last Browser Date Days Notes
webassembly.api.Exception 📋Safari12/13/2021 Firefox5/3/2022141
webassembly.api.Exception.Exception 📋Safari12/13/2021 Firefox5/3/2022141
webassembly.api.Exception.Exception.options_parameter_traceStack Safari12/13/2021 Firefox5/3/2022141
webassembly.api.Exception.getArg 📋Safari12/13/2021 Firefox5/3/2022141
webassembly.api.Exception.is 📋Safari12/13/2021 Firefox5/3/2022141
webassembly.api.Tag 📋Safari12/13/2021 Firefox5/3/2022141
webassembly.api.Tag.Tag 📋Safari12/13/2021 Firefox5/3/2022141
webassembly.exception-handling 📋Safari12/13/2021 Firefox5/3/2022141

2021/12

API First Browser Date Last Browser Date Days Notes
webassembly.api.Memory.Memory.shared 📋Firefox6/30/2020 Safari12/13/2021531
Safari: Shared WebAssembly.Memory is gated behind COOP/COEP. For more detail, read Making your website "cross-origin isolated" using COOP and COEP.Safari on iOS: Shared WebAssembly.Memory is gated behind COOP/COEP. For more detail, read Making your website "cross-origin isolated" using COOP and COEP.WebView on iOS: Shared WebAssembly.Memory is gated behind COOP/COEP. For more detail, read Making your website "cross-origin isolated" using COOP and COEP.
webassembly.threads-and-atomics 📋Firefox7/28/2020 Safari12/13/2021503

2021/10

API First Browser Date Last Browser Date Days Notes
webassembly.bulk-memory-operations 📋Firefox6/30/2020 Safari10/25/2021482
webassembly.non-trapping-float-to-int-conversions 📋Firefox12/11/2018 Safari10/25/20211049
webassembly.reference-types 📋Firefox7/28/2020 Safari10/25/2021454

2021/9

API First Browser Date Last Browser Date Days Notes
webassembly.api.compileStreaming_static 📋Firefox1/23/2018 Safari9/20/20211336
webassembly.api.instantiateStreaming_static 📋Firefox1/23/2018 Safari9/20/20211336

2021/4

API First Browser Date Last Browser Date Days Notes
webassembly.BigInt-to-i64-integration 📋Firefox6/30/2020 Safari4/26/2021300
webassembly.sign-extension-operations 📋Firefox9/5/2018 Safari4/26/2021964

2020/6

API First Browser Date Last Browser Date Days Notes
webassembly.multi-value 📋Safari3/24/2020 Firefox6/30/202098

2020/3

API First Browser Date Last Browser Date Days Notes
webassembly.api.Global 📋Firefox9/5/2018 Safari3/24/2020566
webassembly.api.Global.Global 📋Firefox9/5/2018 Safari3/24/2020566
Chrome: Constructing a Global with a value of v128 produces a TypeError.Chrome Android: Constructing a Global with a value of v128 produces a TypeError.Deno: Constructing a Global with a value of v128 produces a TypeError.Edge: Constructing a Global with a value of v128 produces a TypeError.Node.js: Constructing a Global with a value of v128 produces a TypeError.Quest Browser: Constructing a Global with a value of v128 produces a TypeError.Opera: Constructing a Global with a value of v128 produces a TypeError.Opera Android: Constructing a Global with a value of v128 produces a TypeError.Samsung Internet: Constructing a Global with a value of v128 produces a TypeError.WebView Android: Constructing a Global with a value of v128 produces a TypeError.
webassembly.api.Global.value 📋Firefox9/5/2018 Safari3/24/2020566
webassembly.api.Global.valueOf 📋Firefox9/5/2018 Safari3/24/2020566
webassembly.mutable-globals 📋Firefox9/5/2018 Safari3/24/2020566

2017/9

API First Browser Date Last Browser Date Days Notes
webassembly.api 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.CompileError 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.CompileError.CompileError 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Instance 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Instance.Instance 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Instance.exports 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.LinkError 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.LinkError.LinkError 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Memory 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Memory.Memory 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Memory.buffer 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Memory.grow 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Module 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Module.Module 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Module.customSections_static 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Module.exports_static 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Module.imports_static 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.RuntimeError 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.RuntimeError.RuntimeError 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Table 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Table.Table 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Table.get 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Table.grow 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Table.length 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.Table.set 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.compile_static 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.instantiate_static 📋Firefox3/7/2017 Safari9/19/2017196
webassembly.api.validate_static 📋Firefox3/7/2017 Safari9/19/2017196