diff --git a/Examples/Demo/Demo.xcodeproj/project.pbxproj b/Examples/Demo/Demo.xcodeproj/project.pbxproj
index 557d8250..428242d2 100644
--- a/Examples/Demo/Demo.xcodeproj/project.pbxproj
+++ b/Examples/Demo/Demo.xcodeproj/project.pbxproj
@@ -288,7 +288,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				IPHONEOS_DEPLOYMENT_TARGET = 16.2;
+				IPHONEOS_DEPLOYMENT_TARGET = 26.0;
 				MTL_ENABLE_DEBUG_INFO = INCLUDE_SOURCE;
 				MTL_FAST_MATH = YES;
 				ONLY_ACTIVE_ARCH = YES;
@@ -342,7 +342,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				IPHONEOS_DEPLOYMENT_TARGET = 16.2;
+				IPHONEOS_DEPLOYMENT_TARGET = 26.0;
 				MTL_ENABLE_DEBUG_INFO = NO;
 				MTL_FAST_MATH = YES;
 				SDKROOT = iphoneos;
@@ -360,6 +360,7 @@
 				CODE_SIGN_STYLE = Automatic;
 				CURRENT_PROJECT_VERSION = 1;
 				DEVELOPMENT_ASSET_PATHS = "\"Demo/Preview Content\"";
+				DEVELOPMENT_TEAM = 6Q6JDZK895;
 				ENABLE_PREVIEWS = YES;
 				GENERATE_INFOPLIST_FILE = YES;
 				INFOPLIST_KEY_UIApplicationSceneManifest_Generation = YES;
@@ -367,7 +368,7 @@
 				INFOPLIST_KEY_UILaunchScreen_Generation = YES;
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPad = "UIInterfaceOrientationPortrait UIInterfaceOrientationPortraitUpsideDown UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPhone = "UIInterfaceOrientationPortrait UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
-				IPHONEOS_DEPLOYMENT_TARGET = 16.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 26.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -389,6 +390,7 @@
 				CODE_SIGN_STYLE = Automatic;
 				CURRENT_PROJECT_VERSION = 1;
 				DEVELOPMENT_ASSET_PATHS = "\"Demo/Preview Content\"";
+				DEVELOPMENT_TEAM = 6Q6JDZK895;
 				ENABLE_PREVIEWS = YES;
 				GENERATE_INFOPLIST_FILE = YES;
 				INFOPLIST_KEY_UIApplicationSceneManifest_Generation = YES;
@@ -396,7 +398,7 @@
 				INFOPLIST_KEY_UILaunchScreen_Generation = YES;
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPad = "UIInterfaceOrientationPortrait UIInterfaceOrientationPortraitUpsideDown UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
 				INFOPLIST_KEY_UISupportedInterfaceOrientations_iPhone = "UIInterfaceOrientationPortrait UIInterfaceOrientationLandscapeLeft UIInterfaceOrientationLandscapeRight";
-				IPHONEOS_DEPLOYMENT_TARGET = 16.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 26.0;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
diff --git a/Package.resolved b/Package.resolved
index 1874936d..4ec18605 100644
--- a/Package.resolved
+++ b/Package.resolved
@@ -1,12 +1,13 @@
 {
+  "originHash" : "775133063413f538b6f898bf60cb1bb8a6a0a7c228bf6cf014cef522a89c2168",
   "pins" : [
     {
       "identity" : "networkimage",
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/gonzalezreal/NetworkImage",
       "state" : {
-        "revision" : "7aff8d1b31148d32c5933d75557d42f6323ee3d1",
-        "version" : "6.0.0"
+        "revision" : "2849f5323265386e200484b0d0f896e73c3411b9",
+        "version" : "6.0.1"
       }
     },
     {
@@ -18,15 +19,42 @@
         "version" : "0.5.0"
       }
     },
+    {
+      "identity" : "swift-custom-dump",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/pointfreeco/swift-custom-dump",
+      "state" : {
+        "revision" : "82645ec760917961cfa08c9c0c7104a57a0fa4b1",
+        "version" : "1.3.3"
+      }
+    },
     {
       "identity" : "swift-snapshot-testing",
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/pointfreeco/swift-snapshot-testing",
       "state" : {
-        "revision" : "26ed3a2b4a2df47917ca9b790a57f91285b923fb",
-        "version" : "1.12.0"
+        "revision" : "a8b7c5e0ed33d8ab8887d1654d9b59f2cbad529b",
+        "version" : "1.18.7"
+      }
+    },
+    {
+      "identity" : "swift-syntax",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/swiftlang/swift-syntax",
+      "state" : {
+        "revision" : "4799286537280063c85a32f09884cfbca301b1a1",
+        "version" : "602.0.0"
+      }
+    },
+    {
+      "identity" : "xctest-dynamic-overlay",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/pointfreeco/xctest-dynamic-overlay",
+      "state" : {
+        "revision" : "4c27acf5394b645b70d8ba19dc249c0472d5f618",
+        "version" : "1.7.0"
       }
     }
   ],
-  "version" : 2
+  "version" : 3
 }
diff --git a/Package.swift b/Package.swift
index 5fb61bc9..9217946f 100644
--- a/Package.swift
+++ b/Package.swift
@@ -1,15 +1,16 @@
-// swift-tools-version:5.6
+// swift-tools-version:6.2
 
 import PackageDescription
 
 let package = Package(
   name: "swift-markdown-ui",
   platforms: [
-    .macOS(.v12),
-    .iOS(.v15),
-    .tvOS(.v15),
-    .macCatalyst(.v15),
-    .watchOS(.v8),
+    .macOS(.v26),
+    .iOS(.v26),
+    .tvOS(.v26),
+    .macCatalyst(.v26),
+    .watchOS(.v26),
+    .visionOS(.v26),
   ],
   products: [
     .library(
@@ -18,9 +19,9 @@ let package = Package(
     )
   ],
   dependencies: [
-    .package(url: "https://github.com/gonzalezreal/NetworkImage", from: "6.0.0"),
-    .package(url: "https://github.com/pointfreeco/swift-snapshot-testing", from: "1.10.0"),
-    .package(url: "https://github.com/swiftlang/swift-cmark", from: "0.4.0"),
+    .package(url: "https://github.com/gonzalezreal/NetworkImage", from: "6.0.1"),
+    .package(url: "https://github.com/pointfreeco/swift-snapshot-testing", from: "1.18.7"),
+    .package(url: "https://github.com/swiftlang/swift-cmark", from: "0.5.0"),
   ],
   targets: [
     .target(
diff --git a/README.md b/README.md
index 486e9fee..e6e67d2f 100644
--- a/README.md
+++ b/README.md
@@ -32,13 +32,13 @@ You can use the built-in themes, create your own or override specific text and b
 
 You can use MarkdownUI on the following platforms:
 
-- macOS 12.0+
-- iOS 15.0+
-- tvOS 15.0+
-- watchOS 8.0+
+- macOS 26.0+
+- iOS 26.0+
+- tvOS 26.0+
+- watchOS 26.0+
+- visionOS 26.0+
 
-Some features, like displaying tables or multi-image paragraphs, require macOS 13.0+, iOS 16.0+,
-tvOS 16.0+, and watchOS 9.0+.
+This library has been updated for Swift 6.2 and the latest Apple platforms (2025).
 
 ## Getting started
 
diff --git a/Sources/MarkdownUI/DSL/Inlines/SoftBreak.swift b/Sources/MarkdownUI/DSL/Inlines/SoftBreak.swift
index 95551353..ad49dcd4 100644
--- a/Sources/MarkdownUI/DSL/Inlines/SoftBreak.swift
+++ b/Sources/MarkdownUI/DSL/Inlines/SoftBreak.swift
@@ -13,7 +13,7 @@ public struct SoftBreak: InlineContentProtocol {
 }
 
 extension SoftBreak {
-  public enum Mode {
+  public enum Mode: Sendable {
     /// Treat a soft break as a space
     case space
 
diff --git a/Sources/MarkdownUI/Extensibility/AssetImageProvider.swift b/Sources/MarkdownUI/Extensibility/AssetImageProvider.swift
index abeb0030..e02205aa 100644
--- a/Sources/MarkdownUI/Extensibility/AssetImageProvider.swift
+++ b/Sources/MarkdownUI/Extensibility/AssetImageProvider.swift
@@ -12,16 +12,16 @@ import SwiftUI
 /// }
 /// .markdownImageProvider(.asset)
 /// ```
-public struct AssetImageProvider: ImageProvider {
-  private let name: (URL) -> String
+public struct AssetImageProvider: ImageProvider, Sendable {
+  private let name: @Sendable (URL) -> String
   private let bundle: Bundle?
 
   /// Creates an asset image provider.
   /// - Parameters:
   ///   - name: A closure that extracts the image resource name from the URL in the Markdown content.
-  ///   - bundle: The bundle where the image resources are located. Specify `nil` to search the app’s main bundle.
+  ///   - bundle: The bundle where the image resources are located. Specify `nil` to search the app's main bundle.
   public init(
-    name: @escaping (URL) -> String = \.lastPathComponent,
+    name: @escaping @Sendable (URL) -> String = \.lastPathComponent,
     bundle: Bundle? = nil
   ) {
     self.name = name
diff --git a/Sources/MarkdownUI/Extensibility/AssetInlineImageProvider.swift b/Sources/MarkdownUI/Extensibility/AssetInlineImageProvider.swift
index c88f2fe7..c78ec558 100644
--- a/Sources/MarkdownUI/Extensibility/AssetInlineImageProvider.swift
+++ b/Sources/MarkdownUI/Extensibility/AssetInlineImageProvider.swift
@@ -2,15 +2,15 @@ import SwiftUI
 
 /// An inline image provider that loads images from resources located in an app or a module.
 public struct AssetInlineImageProvider: InlineImageProvider {
-  private let name: (URL) -> String
+  private let name: @Sendable (URL) -> String
   private let bundle: Bundle?
 
   /// Creates an asset inline image provider.
   /// - Parameters:
   ///   - name: A closure that extracts the image resource name from the URL in the Markdown content.
-  ///   - bundle: The bundle where the image resources are located. Specify `nil` to search the app’s main bundle.
+  ///   - bundle: The bundle where the image resources are located. Specify `nil` to search the app's main bundle.
   public init(
-    name: @escaping (URL) -> String = \.lastPathComponent,
+    name: @escaping @Sendable (URL) -> String = \.lastPathComponent,
     bundle: Bundle? = nil
   ) {
     self.name = name
diff --git a/Sources/MarkdownUI/Extensibility/CodeSyntaxHighlighter.swift b/Sources/MarkdownUI/Extensibility/CodeSyntaxHighlighter.swift
index b725dd40..2f431ecf 100644
--- a/Sources/MarkdownUI/Extensibility/CodeSyntaxHighlighter.swift
+++ b/Sources/MarkdownUI/Extensibility/CodeSyntaxHighlighter.swift
@@ -4,7 +4,7 @@ import SwiftUI
 ///
 /// To configure the current code syntax highlighter for a view hierarchy, use the
 /// `markdownCodeSyntaxHighlighter(_:)` modifier.
-public protocol CodeSyntaxHighlighter {
+public protocol CodeSyntaxHighlighter: Sendable {
   /// Returns a text view configured with the syntax highlighted code.
   /// - Parameters:
   ///   - code: The code block.
diff --git a/Sources/MarkdownUI/Extensibility/DefaultImageProvider.swift b/Sources/MarkdownUI/Extensibility/DefaultImageProvider.swift
index cce0c086..dee216ee 100644
--- a/Sources/MarkdownUI/Extensibility/DefaultImageProvider.swift
+++ b/Sources/MarkdownUI/Extensibility/DefaultImageProvider.swift
@@ -2,7 +2,7 @@ import NetworkImage
 import SwiftUI
 
 /// The default image provider, which loads images from the network.
-public struct DefaultImageProvider: ImageProvider {
+public struct DefaultImageProvider: ImageProvider, Sendable {
   public func makeImage(url: URL?) -> some View {
     NetworkImage(url: url) { state in
       switch state {
diff --git a/Sources/MarkdownUI/Extensibility/ImageProvider.swift b/Sources/MarkdownUI/Extensibility/ImageProvider.swift
index 937319b2..32c6937b 100644
--- a/Sources/MarkdownUI/Extensibility/ImageProvider.swift
+++ b/Sources/MarkdownUI/Extensibility/ImageProvider.swift
@@ -26,12 +26,12 @@ public protocol ImageProvider {
   @ViewBuilder func makeImage(url: URL?) -> Body
 }
 
-struct AnyImageProvider: ImageProvider {
-  private let _makeImage: (URL?) -> AnyView
+struct AnyImageProvider: ImageProvider, @unchecked Sendable {
+  private let _makeImage: @Sendable (URL?) -> AnyView
 
-  init<I: ImageProvider>(_ imageProvider: I) {
-    self._makeImage = {
-      AnyView(imageProvider.makeImage(url: $0))
+  init<I: ImageProvider>(_ imageProvider: I) where I: Sendable {
+    self._makeImage = { url in
+      AnyView(imageProvider.makeImage(url: url))
     }
   }
 
diff --git a/Sources/MarkdownUI/Extensibility/InlineImageProvider.swift b/Sources/MarkdownUI/Extensibility/InlineImageProvider.swift
index 06bd9e1c..b4c9c32e 100644
--- a/Sources/MarkdownUI/Extensibility/InlineImageProvider.swift
+++ b/Sources/MarkdownUI/Extensibility/InlineImageProvider.swift
@@ -4,7 +4,7 @@ import SwiftUI
 ///
 /// To configure the current inline image provider for a view hierarchy,
 /// use the `markdownInlineImageProvider(_:)` modifier.
-public protocol InlineImageProvider {
+public protocol InlineImageProvider: Sendable {
   /// Returns an image for the given URL.
   ///
   /// ``Markdown`` views call this method to load images within a line of text.
diff --git a/Sources/MarkdownUI/Theme/BlockStyle/BlockConfiguration.swift b/Sources/MarkdownUI/Theme/BlockStyle/BlockConfiguration.swift
index 0ee2a56d..f032337d 100644
--- a/Sources/MarkdownUI/Theme/BlockStyle/BlockConfiguration.swift
+++ b/Sources/MarkdownUI/Theme/BlockStyle/BlockConfiguration.swift
@@ -8,7 +8,7 @@ import SwiftUI
 public struct BlockConfiguration {
   /// A type-erased view of a Markdown block.
   public struct Label: View {
-    init<L: View>(_ label: L) {
+    public init<L: View>(_ label: L) {
       self.body = AnyView(label)
     }
 
diff --git a/Sources/MarkdownUI/Theme/BlockStyle/BlockStyle.swift b/Sources/MarkdownUI/Theme/BlockStyle/BlockStyle.swift
index 5dee5ca7..05fda364 100644
--- a/Sources/MarkdownUI/Theme/BlockStyle/BlockStyle.swift
+++ b/Sources/MarkdownUI/Theme/BlockStyle/BlockStyle.swift
@@ -37,16 +37,16 @@ import SwiftUI
 /// ```
 ///
 /// ![](CustomBlockquote)
-public struct BlockStyle<Configuration> {
-  private let body: (Configuration) -> AnyView
+public struct BlockStyle<Configuration>: @unchecked Sendable {
+  private let body: @Sendable @MainActor (Configuration) -> AnyView
 
   /// Creates a block style that customizes a block by applying the given body.
   /// - Parameter body: A view builder that returns the customized block.
-  public init<Body: View>(@ViewBuilder body: @escaping (_ configuration: Configuration) -> Body) {
-    self.body = { AnyView(body($0)) }
+  public init<Body: View>(@ViewBuilder body: @escaping @Sendable @MainActor (_ configuration: Configuration) -> Body) {
+    self.body = { @Sendable @MainActor in AnyView(body($0)) }
   }
 
-  func makeBody(configuration: Configuration) -> AnyView {
+  @MainActor func makeBody(configuration: Configuration) -> AnyView {
     self.body(configuration)
   }
 }
@@ -54,8 +54,8 @@ public struct BlockStyle<Configuration> {
 extension BlockStyle where Configuration == Void {
   /// Creates a block style for a block with no content, like a thematic break.
   /// - Parameter body: A view builder that returns the customized block.
-  public init<Body: View>(@ViewBuilder body: @escaping () -> Body) {
-    self.init { _ in
+  public init<Body: View>(@ViewBuilder body: @escaping @Sendable @MainActor () -> Body) {
+    self.init { @Sendable @MainActor _ in
       body()
     }
   }
diff --git a/Sources/MarkdownUI/Theme/BlockStyle/TableBackgroundStyle.swift b/Sources/MarkdownUI/Theme/BlockStyle/TableBackgroundStyle.swift
index 85e86af9..a53a1fc3 100644
--- a/Sources/MarkdownUI/Theme/BlockStyle/TableBackgroundStyle.swift
+++ b/Sources/MarkdownUI/Theme/BlockStyle/TableBackgroundStyle.swift
@@ -27,13 +27,13 @@ import SwiftUI
 /// ```
 ///
 /// ![](CustomTableBackground)
-public struct TableBackgroundStyle {
-  let background: (_ row: Int, _ column: Int) -> AnyShapeStyle
+public struct TableBackgroundStyle: Sendable {
+  let background: @Sendable (_ row: Int, _ column: Int) -> AnyShapeStyle
 
   /// Creates a table background style that customizes table backgrounds by applying a given closure
   /// to the background of each cell.
   /// - Parameter background: A closure that returns a shape style for a given table cell location.
-  public init<S: ShapeStyle>(background: @escaping (_ row: Int, _ column: Int) -> S) {
+  public init<S: ShapeStyle>(background: @escaping @Sendable (_ row: Int, _ column: Int) -> S) {
     self.background = { row, column in
       AnyShapeStyle(background(row, column))
     }
diff --git a/Sources/MarkdownUI/Theme/BlockStyle/TableBorderStyle.swift b/Sources/MarkdownUI/Theme/BlockStyle/TableBorderStyle.swift
index 06a6921a..a6dfe232 100644
--- a/Sources/MarkdownUI/Theme/BlockStyle/TableBorderStyle.swift
+++ b/Sources/MarkdownUI/Theme/BlockStyle/TableBorderStyle.swift
@@ -30,7 +30,7 @@ import SwiftUI
 /// ```
 ///
 /// ![](CustomTableBorders)
-public struct TableBorderStyle {
+public struct TableBorderStyle: Sendable {
   /// The visible table borders.
   public var visibleBorders: TableBorderSelector
 
diff --git a/Sources/MarkdownUI/Theme/TextStyle/Styles/FontProperties.swift b/Sources/MarkdownUI/Theme/TextStyle/Styles/FontProperties.swift
index 10090cd8..e8950d33 100644
--- a/Sources/MarkdownUI/Theme/TextStyle/Styles/FontProperties.swift
+++ b/Sources/MarkdownUI/Theme/TextStyle/Styles/FontProperties.swift
@@ -1,9 +1,9 @@
 import SwiftUI
 
 /// The characteristics of a font.
-public struct FontProperties: Hashable {
+public struct FontProperties: Hashable, Sendable {
   /// The font family.
-  public enum Family: Hashable {
+  public enum Family: Hashable, Sendable {
     /// The system font family.
     case system(Font.Design = .default)
 
@@ -12,7 +12,7 @@ public struct FontProperties: Hashable {
   }
 
   /// The font family variant.
-  public enum FamilyVariant: Hashable {
+  public enum FamilyVariant: Hashable, Sendable {
     /// No variant. Use the current font family.
     case normal
 
@@ -21,7 +21,7 @@ public struct FontProperties: Hashable {
   }
 
   /// The font caps variant.
-  public enum CapsVariant: Hashable {
+  public enum CapsVariant: Hashable, Sendable {
     /// Don't use a font caps variant.
     case normal
 
@@ -36,7 +36,7 @@ public struct FontProperties: Hashable {
   }
 
   /// The font digit variant.
-  public enum DigitVariant: Hashable {
+  public enum DigitVariant: Hashable, Sendable {
     /// Don't use a font digit variant.
     case normal
 
@@ -45,7 +45,7 @@ public struct FontProperties: Hashable {
   }
 
   /// The font style.
-  public enum Style {
+  public enum Style: Sendable {
     /// Don't use a font style.
     case normal
 
@@ -98,11 +98,24 @@ public struct FontProperties: Hashable {
   /// The font width.
   @available(iOS 16.0, macOS 13.0, tvOS 16.0, watchOS 9.0, *)
   public var width: Font.Width {
-    get { (self.widthStorage as? Font.Width) ?? .standard }
-    set { self.widthStorage = newValue }
+    get {
+      if #available(iOS 16.0, macOS 13.0, tvOS 16.0, watchOS 9.0, *) {
+        return (self.widthStorage?.value as? Font.Width) ?? .standard
+      }
+      return .standard
+    }
+    set {
+      if #available(iOS 16.0, macOS 13.0, tvOS 16.0, watchOS 9.0, *) {
+        self.widthStorage = SendableHashable(value: newValue)
+      }
+    }
   }
 
-  private var widthStorage: AnyHashable?
+  private var widthStorage: SendableHashable?
+
+  private struct SendableHashable: Hashable, @unchecked Sendable {
+    let value: AnyHashable
+  }
 
   /// The font size.
   public var size: CGFloat = Self.defaultSize
diff --git a/Sources/MarkdownUI/Theme/TextStyle/TextStyle.swift b/Sources/MarkdownUI/Theme/TextStyle/TextStyle.swift
index 29316dcb..77a7940c 100644
--- a/Sources/MarkdownUI/Theme/TextStyle/TextStyle.swift
+++ b/Sources/MarkdownUI/Theme/TextStyle/TextStyle.swift
@@ -57,6 +57,6 @@ import SwiftUI
 /// ```
 ///
 /// ![](CustomBlockquote)
-public protocol TextStyle {
+public protocol TextStyle: Sendable {
   func _collectAttributes(in attributes: inout AttributeContainer)
 }
diff --git a/Sources/MarkdownUI/Theme/Theme+Basic.swift b/Sources/MarkdownUI/Theme/Theme+Basic.swift
index b5567b59..023c1002 100644
--- a/Sources/MarkdownUI/Theme/Theme+Basic.swift
+++ b/Sources/MarkdownUI/Theme/Theme+Basic.swift
@@ -14,7 +14,7 @@ extension Theme {
   /// Bulleted list | ![](NestedBulletedList)
   /// Numbered list | ![](NumberedList)
   /// Table | ![](Table-Collection)
-  public static let basic = Theme()
+  @MainActor public static let basic = Theme()
     .code {
       FontFamilyVariant(.monospaced)
       FontSize(.em(0.94))
diff --git a/Sources/MarkdownUI/Theme/Theme+DocC.swift b/Sources/MarkdownUI/Theme/Theme+DocC.swift
index 43cf1939..b3010965 100644
--- a/Sources/MarkdownUI/Theme/Theme+DocC.swift
+++ b/Sources/MarkdownUI/Theme/Theme+DocC.swift
@@ -14,7 +14,7 @@ extension Theme {
   /// Bulleted list | ![](DocCNestedBulletedList)
   /// Numbered list | ![](DocCNumberedList)
   /// Table | ![](DocCTable)
-  public static let docC = Theme()
+  @MainActor public static let docC = Theme()
     .text {
       ForegroundColor(.text)
     }
diff --git a/Sources/MarkdownUI/Theme/Theme+GitHub.swift b/Sources/MarkdownUI/Theme/Theme+GitHub.swift
index 90f32ff3..fe1cc040 100644
--- a/Sources/MarkdownUI/Theme/Theme+GitHub.swift
+++ b/Sources/MarkdownUI/Theme/Theme+GitHub.swift
@@ -14,7 +14,7 @@ extension Theme {
   /// Bulleted list | ![](GitHubNestedBulletedList)
   /// Numbered list | ![](GitHubNumberedList)
   /// Table | ![](GitHubTable)
-  public static let gitHub = Theme()
+  @MainActor public static let gitHub = Theme()
     .text {
       ForegroundColor(.text)
       BackgroundColor(.background)
diff --git a/Sources/MarkdownUI/Theme/Theme.swift b/Sources/MarkdownUI/Theme/Theme.swift
index b6d9ca9b..dba19453 100644
--- a/Sources/MarkdownUI/Theme/Theme.swift
+++ b/Sources/MarkdownUI/Theme/Theme.swift
@@ -253,7 +253,7 @@ extension Theme {
   /// Adds a level 1 heading style to the theme.
   /// - Parameter body: A view builder that returns a customized level 1 heading.
   public func heading1<Body: View>(
-    @ViewBuilder body: @escaping (_ configuration: BlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ configuration: BlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.heading1 = .init(body: body)
@@ -263,7 +263,7 @@ extension Theme {
   /// Adds a level 2 heading style to the theme.
   /// - Parameter body: A view builder that returns a customized level 2 heading.
   public func heading2<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.heading2 = .init(body: body)
@@ -273,7 +273,7 @@ extension Theme {
   /// Adds a level 3 heading style to the theme.
   /// - Parameter body: A view builder that returns a customized level 3 heading.
   public func heading3<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.heading3 = .init(body: body)
@@ -283,7 +283,7 @@ extension Theme {
   /// Adds a level 4 heading style to the theme.
   /// - Parameter body: A view builder that returns a customized level 4 heading.
   public func heading4<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.heading4 = .init(body: body)
@@ -293,7 +293,7 @@ extension Theme {
   /// Adds a level 5 heading style to the theme.
   /// - Parameter body: A view builder that returns a customized level 5 heading.
   public func heading5<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.heading5 = .init(body: body)
@@ -303,7 +303,7 @@ extension Theme {
   /// Adds a level 6 heading style to the theme.
   /// - Parameter body: A view builder that returns a customized level 6 heading.
   public func heading6<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.heading6 = .init(body: body)
@@ -313,7 +313,7 @@ extension Theme {
   /// Adds a paragraph style to the theme.
   /// - Parameter body: A view builder that returns a customized paragraph.
   public func paragraph<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.paragraph = .init(body: body)
@@ -323,7 +323,7 @@ extension Theme {
   /// Adds a blockquote style to the theme.
   /// - Parameter body: A view builder that returns a customized blockquote.
   public func blockquote<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.blockquote = .init(body: body)
@@ -333,7 +333,7 @@ extension Theme {
   /// Adds a code block style to the theme.
   /// - Parameter body: A view builder that returns a customized code block.
   public func codeBlock<Body: View>(
-    @ViewBuilder body: @escaping (_ configuration: CodeBlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ configuration: CodeBlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.codeBlock = .init(body: body)
@@ -343,7 +343,7 @@ extension Theme {
   /// Adds an image style to the theme.
   /// - Parameter body: A view builder that returns a customized image.
   public func image<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.image = .init(body: body)
@@ -353,7 +353,7 @@ extension Theme {
   /// Adds a list style to the theme.
   /// - Parameter body: A view builder that returns a customized list.
   public func list<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.list = .init(body: body)
@@ -363,7 +363,7 @@ extension Theme {
   /// Adds a list item style to the theme.
   /// - Parameter body: A view builder that returns a customized list item.
   public func listItem<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.listItem = .init(body: body)
@@ -381,7 +381,7 @@ extension Theme {
   /// Adds a task list marker style to the theme.
   /// - Parameter body: A view builder that returns a customized task list marker.
   public func taskListMarker<Body: View>(
-    @ViewBuilder body: @escaping (_ configuration: TaskListMarkerConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ configuration: TaskListMarkerConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.taskListMarker = .init(body: body)
@@ -401,7 +401,7 @@ extension Theme {
   /// Adds a bulleted list marker style to the theme.
   /// - Parameter body: A view builder that returns a customized bulleted list marker.
   public func bulletedListMarker<Body: View>(
-    @ViewBuilder body: @escaping (_ configuration: ListMarkerConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ configuration: ListMarkerConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.bulletedListMarker = .init(body: body)
@@ -421,7 +421,7 @@ extension Theme {
   /// Adds a numbered list marker style to the theme.
   /// - Parameter body: A view builder that returns a customized numbered list marker.
   public func numberedListMarker<Body: View>(
-    @ViewBuilder body: @escaping (_ configuration: ListMarkerConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ configuration: ListMarkerConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.numberedListMarker = .init(body: body)
@@ -431,7 +431,7 @@ extension Theme {
   /// Adds a table style to the theme.
   /// - Parameter body: A view builder that returns a customized table.
   public func table<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.table = .init(body: body)
@@ -441,7 +441,7 @@ extension Theme {
   /// Adds a table cell style to the theme.
   /// - Parameter body: A view builder that returns a customized table cell.
   public func tableCell<Body: View>(
-    @ViewBuilder body: @escaping (_ configuration: TableCellConfiguration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ configuration: TableCellConfiguration) -> Body
   ) -> Theme {
     var theme = self
     theme.tableCell = .init(body: body)
@@ -450,7 +450,7 @@ extension Theme {
 
   /// Adds a thematic break style to the theme.
   /// - Parameter body: A view builder that returns a customized thematic break.
-  public func thematicBreak<Body: View>(@ViewBuilder body: @escaping () -> Body) -> Theme {
+  public func thematicBreak<Body: View>(@ViewBuilder body: @escaping @Sendable @MainActor () -> Body) -> Theme {
     var theme = self
     theme.thematicBreak = .init(body: body)
     return theme
diff --git a/Sources/MarkdownUI/Utility/Deprecations.swift b/Sources/MarkdownUI/Utility/Deprecations.swift
index 7a60dffa..01bb34e0 100644
--- a/Sources/MarkdownUI/Utility/Deprecations.swift
+++ b/Sources/MarkdownUI/Utility/Deprecations.swift
@@ -25,9 +25,9 @@ extension BlockStyle where Configuration == BlockConfiguration {
     message: "Use the initializer that takes a closure receiving a 'Configuration' value."
   )
   public init<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) {
-    self.init { configuration in
+    self.init { @Sendable @MainActor configuration in
       body(configuration.label)
     }
   }
@@ -38,7 +38,7 @@ extension BlockStyle where Configuration == BlockConfiguration {
     message: "Use the initializer that takes a closure receiving a 'Configuration' value."
   )
   public init() {
-    self.init { $0 }
+    self.init { @Sendable @MainActor in $0 }
   }
 }
 
@@ -53,9 +53,11 @@ extension View {
   )
   public func markdownBlockStyle<Body: View>(
     _ keyPath: WritableKeyPath<Theme, BlockStyle<BlockConfiguration>>,
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> some View {
-    self.environment((\EnvironmentValues.theme).appending(path: keyPath), .init(body: body))
+    self.transformEnvironment(\.theme) { theme in
+      theme[keyPath: keyPath] = .init(body: body)
+    }
   }
 
   @available(
@@ -68,14 +70,13 @@ extension View {
   )
   public func markdownBlockStyle<Body: View>(
     _ keyPath: WritableKeyPath<Theme, BlockStyle<CodeBlockConfiguration>>,
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> some View {
-    self.environment(
-      (\EnvironmentValues.theme).appending(path: keyPath),
-      .init { configuration in
-        body(.init(configuration.label))
+    self.transformEnvironment(\.theme) { theme in
+      theme[keyPath: keyPath] = .init { configuration in
+        body(BlockConfiguration.Label(configuration.label))
       }
-    )
+    }
   }
 }
 
@@ -89,7 +90,7 @@ extension Theme {
       """
   )
   public func heading1<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.heading1 = .init(body: body)
@@ -105,7 +106,7 @@ extension Theme {
       """
   )
   public func heading2<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.heading2 = .init(body: body)
@@ -121,7 +122,7 @@ extension Theme {
       """
   )
   public func heading3<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.heading3 = .init(body: body)
@@ -137,7 +138,7 @@ extension Theme {
       """
   )
   public func heading4<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.heading4 = .init(body: body)
@@ -153,7 +154,7 @@ extension Theme {
       """
   )
   public func heading5<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.heading5 = .init(body: body)
@@ -169,7 +170,7 @@ extension Theme {
       """
   )
   public func heading6<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.heading6 = .init(body: body)
@@ -185,7 +186,7 @@ extension Theme {
       """
   )
   public func paragraph<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.paragraph = .init(body: body)
@@ -201,7 +202,7 @@ extension Theme {
       """
   )
   public func blockquote<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.blockquote = .init(body: body)
@@ -217,7 +218,7 @@ extension Theme {
       """
   )
   public func codeBlock<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.codeBlock = .init { configuration in
@@ -235,7 +236,7 @@ extension Theme {
       """
   )
   public func image<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.image = .init(body: body)
@@ -251,7 +252,7 @@ extension Theme {
       """
   )
   public func list<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.list = .init(body: body)
@@ -267,7 +268,7 @@ extension Theme {
       """
   )
   public func listItem<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.listItem = .init(body: body)
@@ -283,7 +284,7 @@ extension Theme {
       """
   )
   public func table<Body: View>(
-    @ViewBuilder body: @escaping (_ label: BlockConfiguration.Label) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ label: BlockConfiguration.Label) -> Body
   ) -> Theme {
     var theme = self
     theme.table = .init(body: body)
diff --git a/Sources/MarkdownUI/Utility/RelativeSize.swift b/Sources/MarkdownUI/Utility/RelativeSize.swift
index 36ee9bfb..95626810 100644
--- a/Sources/MarkdownUI/Utility/RelativeSize.swift
+++ b/Sources/MarkdownUI/Utility/RelativeSize.swift
@@ -21,8 +21,8 @@ import SwiftUI
 ///     FontSize(.em(2))
 ///   }
 /// ```
-public struct RelativeSize: Hashable {
-  enum Unit: Hashable {
+public struct RelativeSize: Hashable, Sendable {
+  enum Unit: Hashable, Sendable {
     case em
     case rem
   }
diff --git a/Sources/MarkdownUI/Views/Blocks/TableBorderSelector.swift b/Sources/MarkdownUI/Views/Blocks/TableBorderSelector.swift
index 9b85d8a0..e1a27163 100644
--- a/Sources/MarkdownUI/Views/Blocks/TableBorderSelector.swift
+++ b/Sources/MarkdownUI/Views/Blocks/TableBorderSelector.swift
@@ -3,8 +3,8 @@ import SwiftUI
 /// A type that selects the visible borders on a Markdown table.
 ///
 /// You use a table border selector to select the visible borders when creating a ``TableBorderStyle``.
-public struct TableBorderSelector {
-  var rectangles: (_ tableBounds: TableBounds, _ borderWidth: CGFloat) -> [CGRect]
+public struct TableBorderSelector: @unchecked Sendable {
+  var rectangles: @Sendable (_ tableBounds: TableBounds, _ borderWidth: CGFloat) -> [CGRect]
 }
 
 extension TableBorderSelector {
diff --git a/Sources/MarkdownUI/Views/Environment/Environment+BaseURL.swift b/Sources/MarkdownUI/Views/Environment/Environment+BaseURL.swift
index 9eb4f852..92316510 100644
--- a/Sources/MarkdownUI/Views/Environment/Environment+BaseURL.swift
+++ b/Sources/MarkdownUI/Views/Environment/Environment+BaseURL.swift
@@ -13,9 +13,9 @@ extension EnvironmentValues {
 }
 
 private struct BaseURLKey: EnvironmentKey {
-  static var defaultValue: URL? = nil
+  static let defaultValue: URL? = nil
 }
 
 private struct ImageBaseURLKey: EnvironmentKey {
-  static var defaultValue: URL? = nil
+  static let defaultValue: URL? = nil
 }
diff --git a/Sources/MarkdownUI/Views/Environment/Environment+ImageProvider.swift b/Sources/MarkdownUI/Views/Environment/Environment+ImageProvider.swift
index 909f1e4f..333301af 100644
--- a/Sources/MarkdownUI/Views/Environment/Environment+ImageProvider.swift
+++ b/Sources/MarkdownUI/Views/Environment/Environment+ImageProvider.swift
@@ -7,7 +7,7 @@ extension View {
   ///                            or a custom image provider that you define by creating a type that
   ///                            conforms to the ``ImageProvider`` protocol.
   /// - Returns: A view that uses the specified image provider for itself and its child views.
-  public func markdownImageProvider<I: ImageProvider>(_ imageProvider: I) -> some View {
+  public func markdownImageProvider<I: ImageProvider>(_ imageProvider: I) -> some View where I: Sendable {
     self.environment(\.imageProvider, .init(imageProvider))
   }
 }
diff --git a/Sources/MarkdownUI/Views/Environment/Environment+List.swift b/Sources/MarkdownUI/Views/Environment/Environment+List.swift
index 46ea6343..9d9eca58 100644
--- a/Sources/MarkdownUI/Views/Environment/Environment+List.swift
+++ b/Sources/MarkdownUI/Views/Environment/Environment+List.swift
@@ -13,9 +13,9 @@ extension EnvironmentValues {
 }
 
 private struct ListLevelKey: EnvironmentKey {
-  static var defaultValue = 0
+  static let defaultValue = 0
 }
 
 private struct TightSpacingEnabledKey: EnvironmentKey {
-  static var defaultValue = false
+  static let defaultValue = false
 }
diff --git a/Sources/MarkdownUI/Views/Environment/Environment+Theme.swift b/Sources/MarkdownUI/Views/Environment/Environment+Theme.swift
index 7fd986a3..be60fa3b 100644
--- a/Sources/MarkdownUI/Views/Environment/Environment+Theme.swift
+++ b/Sources/MarkdownUI/Views/Environment/Environment+Theme.swift
@@ -15,7 +15,10 @@ extension View {
     _ keyPath: WritableKeyPath<Theme, TextStyle>,
     @TextStyleBuilder textStyle: () -> S
   ) -> some View {
-    self.environment((\EnvironmentValues.theme).appending(path: keyPath), textStyle())
+    let style = textStyle()
+    return self.transformEnvironment(\.theme) { theme in
+      theme[keyPath: keyPath] = style
+    }
   }
 
   /// Replaces a specific block style on the current ``Theme`` with a block style initialized with the given body closure.
@@ -24,9 +27,11 @@ extension View {
   ///   - body: A view builder that returns the customized block.
   public func markdownBlockStyle<Body: View>(
     _ keyPath: WritableKeyPath<Theme, BlockStyle<Void>>,
-    @ViewBuilder body: @escaping () -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor () -> Body
   ) -> some View {
-    self.environment((\EnvironmentValues.theme).appending(path: keyPath), .init(body: body))
+    self.transformEnvironment(\.theme) { theme in
+      theme[keyPath: keyPath] = BlockStyle<Void>(body: body)
+    }
   }
 
   /// Replaces a specific block style on the current ``Theme`` with a block style initialized with the given body closure.
@@ -35,9 +40,11 @@ extension View {
   ///   - body: A view builder that receives the block configuration and returns the customized block.
   public func markdownBlockStyle<Configuration, Body: View>(
     _ keyPath: WritableKeyPath<Theme, BlockStyle<Configuration>>,
-    @ViewBuilder body: @escaping (_ configuration: Configuration) -> Body
+    @ViewBuilder body: @escaping @Sendable @MainActor (_ configuration: Configuration) -> Body
   ) -> some View {
-    self.environment((\EnvironmentValues.theme).appending(path: keyPath), .init(body: body))
+    self.transformEnvironment(\.theme) { theme in
+      theme[keyPath: keyPath] = BlockStyle<Configuration>(body: body)
+    }
   }
 
   /// Replaces the current ``Theme`` task list marker with the given list marker.
@@ -70,5 +77,5 @@ extension EnvironmentValues {
 }
 
 private struct ThemeKey: EnvironmentKey {
-  static let defaultValue: Theme = .basic
+  nonisolated(unsafe) static let defaultValue: Theme = Theme()
 }