@@ -26,6 +26,8 @@ export default defineConfig({
   use: {
     /* Base URL to use in actions like `await page.goto('')`. */
     baseURL: testBaseUrl,
+    /* The preview copy button writes to the clipboard. */
+    permissions: ["clipboard-read", "clipboard-write"],
   },
 
   /* Configure projects for major browsers */
 
@@ -1,4 +1,45 @@
-import { typstMockState } from "/pptypst/__test__/typst-state.js";
+/**
+ * Browser mock for `@myriaddreamin/typst.ts`.
+ *
+ * `TypstMock` (see ../typst-mock.ts) serves this in place of the real
+ * WASM-backed library. Recorded compiler/renderer calls and the SVG the
+ * renderer returns live on `window.__typstMock` so the Node-side helper can
+ * read and tweak them via `page.evaluate`.
+ */
+
+export type TypstMockState = {
+  rendererInitOptions: { hasGetModule: boolean }[];
+  addSourceCalls: { path: string; source: string }[];
+  compileCalls: { mainFilePath: string }[];
+  renderSvgCalls: {
+    format: string;
+    artifactContent: number[];
+    data_selection: Record<string, boolean>;
+  }[];
+  previewSvg: string;
+};
+
+declare global {
+  interface Window {
+    __typstMock?: TypstMockState;
+  }
+}
+
+const DEFAULT_PREVIEW_SVG = [
+  '<svg xmlns="http://www.w3.org/2000/svg" width="160" height="40">',
+  '<text x="0" y="20" fill="#000">integral preview</text>',
+  "</svg>",
+].join("");
+
+const state: TypstMockState = {
+  rendererInitOptions: [],
+  addSourceCalls: [],
+  compileCalls: [],
+  renderSvgCalls: [],
+  previewSvg: DEFAULT_PREVIEW_SVG,
+};
+
+window.__typstMock = state;
 
 type CompilerInitOptions = { beforeBuild: unknown[]; getModule: unknown };
 type CompileOptions = { mainFilePath: string };
@@ -8,12 +49,6 @@ type RenderSvgOptions = {
   data_selection: Record<string, boolean>;
 };
 
-const previewSvg = [
-  '<svg xmlns="http://www.w3.org/2000/svg" width="160" height="40">',
-  '<text x="0" y="20" fill="#000">integral preview</text>',
-  "</svg>",
-].join("");
-
 export function createTypstCompiler() {
   return {
     init(options: CompilerInitOptions) {
@@ -25,10 +60,10 @@ export function createTypstCompiler() {
       return Promise.resolve();
     },
     addSource(path: string, source: string) {
-      typstMockState.addSourceCalls.push({ path, source });
+      state.addSourceCalls.push({ path, source });
     },
     compile(options: CompileOptions) {
-      typstMockState.compileCalls.push(options);
+      state.compileCalls.push(options);
       return Promise.resolve({ diagnostics: [], result: new Uint8Array([1, 2, 3]) });
     },
   };
@@ -37,16 +72,16 @@ export function createTypstCompiler() {
 export function createTypstRenderer() {
   return {
     init(options: { getModule: unknown }) {
-      typstMockState.rendererInitOptions.push({ hasGetModule: typeof options.getModule === "function" });
+      state.rendererInitOptions.push({ hasGetModule: typeof options.getModule === "function" });
       return Promise.resolve();
     },
     renderSvg(options: RenderSvgOptions) {
-      typstMockState.renderSvgCalls.push({
+      state.renderSvgCalls.push({
         format: options.format,
         artifactContent: Array.from(options.artifactContent),
         data_selection: options.data_selection,
       });
-      return Promise.resolve(previewSvg);
+      return Promise.resolve(state.previewSvg);
     },
   };
 }
@@ -1,18 +1,12 @@
 import type { Page } from "@playwright/test";
 import path from "node:path";
 import { compileBrowserMock } from "./transpile-browser-mock";
+import type { TypstMockState } from "./browser-mocks/typst";
 
-export type TypstMockCalls = {
-  addSourceCalls: { path: string; source: string }[];
-  compileCalls: { mainFilePath: string }[];
-  renderSvgCalls: {
-    format: string;
-    artifactContent: number[];
-    data_selection: Record<string, boolean>;
-  }[];
-};
-
-const stateModuleUrl = "/pptypst/__test__/typst-state.js";
+export type TypstMockCalls = Pick<
+  TypstMockState,
+  "addSourceCalls" | "compileCalls" | "renderSvgCalls"
+>;
 
 function browserMockPath(fileName: string) {
   return path.join(process.cwd(), "tests", "_support", "browser-mocks", fileName);
@@ -28,7 +22,6 @@ export class TypstMock {
 
   /** Routes only the Typst modules that web/src/typst.ts and font-cache.ts import. */
   async install() {
-    await this.routeModule("**/__test__/typst-state.js", "typst-state.ts");
     await this.routeModule("**/@myriaddreamin_typst__ts.js*", "typst.ts");
     await this.routeModule("**/@myriaddreamin_typst__ts_dist_esm_options__init__mjs.js*", "typst-options.ts");
     await this.routeModule("**/@myriaddreamin_typst__ts_dist_esm_fs_package__node__mjs.js*", "typst-package-registry.ts");
@@ -37,24 +30,34 @@ export class TypstMock {
     await this.routeModule("**/typst_ts_renderer_bg.wasm?*", "typst-wasm-url.ts");
   }
 
-  /** Waits for the mocked renderer init call, which means the Typst wrapper initialized. */
+  /** Resolves once the app has initialized the mocked renderer. */
   async waitUntilReady() {
-    await this.page.waitForFunction(async (moduleUrl) => {
-      const stateModule = await import(moduleUrl) as {
-        typstMockReady: () => boolean;
-      };
-      return stateModule.typstMockReady();
-    }, stateModuleUrl);
+    await this.page.waitForFunction(
+      () => window.__typstMock?.rendererInitOptions.length === 1,
+    );
   }
 
-  /** Returns the Typst compiler and renderer calls recorded in the browser. */
+  /** Snapshot of the compiler/renderer calls recorded so far. */
   async calls(): Promise<TypstMockCalls> {
-    return this.page.evaluate(async (moduleUrl) => {
-      const stateModule = await import(moduleUrl) as {
-        typstMockCalls: () => TypstMockCalls;
-      };
-      return stateModule.typstMockCalls();
-    }, stateModuleUrl);
+    return this.page.evaluate(() => {
+      const state = window.__typstMock;
+      if (!state) {
+        throw new Error("Typst mock has not been initialized yet.");
+      }
+      const { addSourceCalls, compileCalls, renderSvgCalls } = state;
+      return { addSourceCalls, compileCalls, renderSvgCalls };
+    });
+  }
+
+  /** Overrides the SVG the mocked renderer returns for subsequent preview renders. */
+  async setPreviewSvg(svg: string) {
+    await this.page.evaluate((value) => {
+      const state = window.__typstMock;
+      if (!state) {
+        throw new Error("Typst mock has not been initialized yet.");
+      }
+      state.previewSvg = value;
+    }, svg);
   }
 
   private async routeModule(url: string, fileName: string) {
 
@@ -49,6 +49,7 @@ export type OfficeSnapshot = {
 
 type OfficeMockWindow = Window & typeof globalThis & {
   __pptypstOfficeSeed?: OfficeMockSeed;
+  __pptypstClipboardWriteTypes?: string[];
   __pptypstOfficeMock: {
     reset: (_seed?: OfficeMockSeed) => void;
     selectShapes: (_slideId: string, _shapeIds: string[]) => Promise<void>;
@@ -123,6 +124,10 @@ export class PowerPointPage {
     await this.page.locator("#fillColor").fill(fillColor);
   }
 
+  async setPreviewTypstFillEnabled(enabled: boolean) {
+    await this.page.locator("#previewFillEnabled").setChecked(enabled);
+  }
+
   async insertOrUpdate() {
     await this.page.locator("#insertBtn").click();
   }
@@ -131,6 +136,39 @@ export class PowerPointPage {
     await this.page.locator("#bulkUpdateBtn").click();
   }
 
+  async copyPreviewSvg(options: { invertColors?: boolean } = {}) {
+    await this.page.locator("#previewCopyBtn").click({
+      modifiers: options.invertColors ? ["Shift"] : [],
+    });
+  }
+
+  async readClipboardText(): Promise<string> {
+    return this.page.evaluate(() => navigator.clipboard.readText());
+  }
+
+  async recordClipboardWrites() {
+    await this.page.evaluate(() => {
+      const appWindow = window as OfficeMockWindow;
+      const originalWriteText = navigator.clipboard.writeText.bind(navigator.clipboard);
+      Object.defineProperty(navigator.clipboard, "write", {
+        configurable: true,
+        value: async (items: ClipboardItem[]) => {
+          appWindow.__pptypstClipboardWriteTypes = items.flatMap(item => item.types);
+          const firstItem = items[0];
+          const textBlob = await firstItem.getType("text/plain");
+          await originalWriteText(await textBlob.text());
+        },
+      });
+    });
+  }
+
+  async clipboardWriteTypes(): Promise<string[]> {
+    return this.page.evaluate(() => {
+      const appWindow = window as OfficeMockWindow;
+      return appWindow.__pptypstClipboardWriteTypes || [];
+    });
+  }
+
   async selectShapes(slideId: string, shapeIds: string[]) {
     await this.page.evaluate(
       async ({ selectedSlideId, selectedShapeIds }) => {
 
@@ -31,3 +31,60 @@ test("previews Typst math expressions", async ({ powerPointPage, typstMock }) =>
     },
   ]);
 });
+
+test("copies the preview SVG with optional inverted colors", async ({ powerPointPage }) => {
+  await powerPointPage.previewExpression("integral_a^b f(x) dif x");
+  await powerPointPage.expectPreviewVisible();
+
+  await powerPointPage.recordClipboardWrites();
+  await powerPointPage.copyPreviewSvg();
+  await expect.poll(() => powerPointPage.readClipboardText()).toContain('fill="#000000"');
+  const copiedSvg = await powerPointPage.readClipboardText();
+  await expect.poll(() => powerPointPage.clipboardWriteTypes()).toEqual([
+    "image/svg+xml",
+    "text/plain",
+  ]);
+  expect(copiedSvg).toContain("<svg");
+  expect(copiedSvg).toContain("integral preview");
+  expect(copiedSvg).toContain('fill="#000000"');
+  expect(copiedSvg).not.toContain('style="width: 100%');
+
+  await powerPointPage.copyPreviewSvg({ invertColors: true });
+  await expect.poll(() => powerPointPage.readClipboardText()).toContain('fill="#ffffff"');
+  const invertedSvg = await powerPointPage.readClipboardText();
+  expect(invertedSvg).toContain("integral preview");
+  expect(invertedSvg).toContain('fill="#ffffff"');
+  expect(invertedSvg).not.toContain('fill="#000000"');
+});
+
+test("copies preview SVGs with alpha fills normalized for compatibility",
+  async ({ powerPointPage, typstMock }) => {
+    await typstMock.setPreviewSvg([
+      '<svg xmlns="http://www.w3.org/2000/svg" width="196.39001" height="93.14115">',
+      '<path fill="#ff000032" stroke="#000" d="M 0 0 L 10 0 L 10 10 Z"/>',
+      '<path fill="#0000ff32" stroke="#000" d="M 20 0 L 30 0 L 30 10 Z"/>',
+      '<path style="fill: #00ff0080; stroke: #00000080" d="M 40 0 L 50 0 L 50 10 Z"/>',
+      "</svg>",
+    ].join(""));
+
+    await powerPointPage.setFillColor(null);
+    await powerPointPage.setPreviewTypstFillEnabled(true);
+    await powerPointPage.previewExpression("compatibility check");
+    await powerPointPage.expectPreviewVisible();
+
+    await powerPointPage.copyPreviewSvg();
+    await expect.poll(() => powerPointPage.readClipboardText())
+      .toContain('fill-opacity="0.19607843137254902"');
+
+    const copiedSvg = await powerPointPage.readClipboardText();
+    expect(copiedSvg).toContain('fill="#ff0000"');
+    expect(copiedSvg).toContain('fill="#0000ff"');
+    expect(copiedSvg).toContain('fill-opacity="0.19607843137254902"');
+    expect(copiedSvg).toContain("fill: rgb(0, 255, 0);");
+    expect(copiedSvg).toContain("fill-opacity: 0.5;");
+    expect(copiedSvg).toContain("stroke-opacity: 0.5;");
+    expect(copiedSvg).not.toContain("#ff000032");
+    expect(copiedSvg).not.toContain("#0000ff32");
+    expect(copiedSvg).not.toContain("#00ff0080");
+    expect(copiedSvg).not.toContain("#00000080");
+  });