feat(docs): drop a note for iOS26 swiftui view masking (#14088)

Author: ioannisj

contents/docs/session-replay/_snippets/ios-installation.mdx

@@ -10,6 +10,13 @@ export const EnableSessionReplayLight = "https://res.cloudinary.com/dmukukwp6/im
 > - Requires PostHog iOS SDK version >= [3.6.0](https://github.com/PostHog/posthog-ios/releases), and it's recommended to always use [the latest version](/docs/sdk-doctor).
 > - Session replay is currently only available on iOS. For future macOS support, please follow and upvote [this GitHub issue](https://github.com/PostHog/posthog-ios/issues/200).
 
+<CalloutBox title="Xcode 26" type="caution" icon="IconWarning">
+
+SwiftUI rendering behavior changed for apps built with Xcode 26 (when running on iOS 26).
+If you're building with Xcode 26, please use PostHog iOS SDK version &gt;= [3.36.1](https://github.com/PostHog/posthog-ios/releases/tag/3.36.1), which includes a partial fix for this issue.
+
+</CalloutBox>
+
 ## Step two: Enable session recordings in your project settings
 
 Enable session recordings in your PostHog [Project Settings](https://app.posthog.com/project/settings).

contents/docs/session-replay/_snippets/ios-privacy.mdx

@@ -26,6 +26,21 @@ imvProfilePhoto.accessibilityIdentifier = "ph-no-capture"
     .postHogNoMask()
   ```
 
+
+<CalloutBox title="SwiftUI and Xcode 26" type="caution" icon="IconInfo">
+
+SwiftUI rendering behavior changed for apps built with Xcode 26 (including when running on iOS 26).
+This affects how SwiftUI maps to UIKit. As a result, the view modifiers `postHogMask()` and `postHogNoMask()` may behave inconsistently for primitive SwiftUI views like `Text`, `Image`, and `Button`.
+
+If you rely on these modifiers for privacy, we recommend validating masking after upgrading Xcode:
+
+- Text inputs like `TextField`, `TextEditor`, `SecureField` and custom views are not affected by this change.
+- For primitive views, try masking a parent view instead.
+- Use `ph-no-capture` tagging for UIKit-backed views.
+- Stop and restart session recording around sensitive screens.
+
+</CalloutBox>
+
 ### Handling sensitive third-party screens
 
 Third-party components (like payment forms or authentication screens) are often rendered in separate view hierarchies that can't be accessed or modified for masking.

contents/docs/session-replay/installation/ios.mdx

@@ -11,6 +11,13 @@ import IOSInstall from "../../integrate/_snippets/install-ios.mdx"
 export const EnableSessionReplayDark = "https://res.cloudinary.com/dmukukwp6/image/upload/posthog.com/contents/images/docs/session-replay/enable-session-replay-in-project-settings-dark-mode.png"
 export const EnableSessionReplayLight = "https://res.cloudinary.com/dmukukwp6/image/upload/posthog.com/contents/images/docs/session-replay/enable-session-replay-in-project-settings-light-mode.png"
 
+<CalloutBox title="Xcode 26" type="caution" icon="IconWarning">
+
+SwiftUI rendering behavior changed for apps built with Xcode 26 (when running on iOS 26).
+If you're building with Xcode 26, please use PostHog iOS SDK version &gt;= [3.36.1](https://github.com/PostHog/posthog-ios/releases/tag/3.36.1), which includes a partial fix for this issue.
+
+</CalloutBox>
+
 <Steps>
 
 <Step title="Add PostHog to your app" badge="required">