index.md

title	slug	tags
Firefox 103 for developers	Mozilla/Firefox/Releases/103	103 Firefox Mozilla Release

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This article provides information about the changes in Firefox 103 that will affect developers. Firefox 103 is the current Beta version of Firefox and will ship on July 26, 2022.

Changes for web developers

Developer Tools

HTML

Removals

CSS

Removals

JavaScript

• Native Error types can now be serialized using the structured clone algorithm. This includes {{JSxRef("Error")}}, {{JSxRef("EvalError")}}, {{JSxRef("RangeError")}}, {{JSxRef("ReferenceError")}}, {{JSxRef("SyntaxError")}}, {{JSxRef("TypeError")}}, {{JSxRef("URIError")}} and {{JSxRef("AggregateError")}}. Serialized properties include the name, message, cause, fileName, lineNumber and columnNumber. For {{JSxRef("AggregateError")}} the message, name, cause and errors properties are serialized. See {{bug(1556604)}} for more details.

Removals

HTTP

Removals

Security

Removals

APIs

• ReadableStream, WritableStream, TransformStream are now Transferable objects, which means that ownership can be transferred when sharing the objects between a window and workers using postMessage, or when using structuredClone() to copy an object. After transferring, the original object cannot be used. See {{bug(1659025)}} for more details.

• caches, CacheStorage, and Cache now require a secure context; the properties/interfaces are not defined if used in an insecure context. Previously cache would return a CacheStorage that would throw an exception if used outside of a secure context. See {{bug(1112134)}} for more details.

DOM

Media, WebRTC, and Web Audio

Removals

WebAssembly

Removals

WebDriver conformance (WebDriver BiDi, Marionette)

Removals

Changes for add-on developers

Removals

Other

Older versions

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