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## 2.86.3

**`(fix):`** XML-encoded (TwiML) types now return their XML representation from
`ToString()` instead of JSON, and `ToXml()` prepends the
`<?xml version="1.0" encoding="utf-8"?>` declaration by default.
Pass `ToXml(xmlDeclaration: false)` to omit it.

## 2.86.2

**`(fix):`** Fix `RequestOptions.AdditionalBodyProperties` throwing `InvalidOperationException` on endpoints
without a request body (e.g. GET requests). When the request body is null, the additional
properties are now sent as the JSON request body.

**`(fix):`** `RequestOptions.AdditionalBodyProperties` is now applied to form-urlencoded requests. The additional
properties are merged into the form body (the additional property wins on a key collision) before
encoding. Multipart requests remain unsupported.