diff --git a/src/server/snapshot/snapshotterInjected.ts b/src/server/snapshot/snapshotterInjected.ts
index 2004c556f8..27db1ff823 100644
--- a/src/server/snapshot/snapshotterInjected.ts
+++ b/src/server/snapshot/snapshotterInjected.ts
@@ -443,8 +443,8 @@ export function frameSnapshotStreamer(snapshotStreamer: string) {
         doctype: document.doctype ? document.doctype.name : undefined,
         resourceOverrides: [],
         viewport: {
-          width: Math.max(document.body ? document.body.offsetWidth : 0, document.documentElement ? document.documentElement.offsetWidth : 0),
-          height: Math.max(document.body ? document.body.offsetHeight : 0, document.documentElement ? document.documentElement.offsetHeight : 0),
+          width: window.innerWidth,
+          height: window.innerHeight,
         },
         url: location.href,
         timestamp,
diff --git a/src/server/trace/recorder/tracing.ts b/src/server/trace/recorder/tracing.ts
index 60cd64e5eb..bd63f2374c 100644
--- a/src/server/trace/recorder/tracing.ts
+++ b/src/server/trace/recorder/tracing.ts
@@ -36,7 +36,7 @@ export type TracerOptions = {
   screenshots?: boolean;
 };
 
-export const VERSION = 1;
+export const VERSION = 2;
 
 type RecordingState = {
   options: TracerOptions,
diff --git a/src/server/trace/viewer/traceModel.ts b/src/server/trace/viewer/traceModel.ts
index 46c9397a9d..c259fe5433 100644
--- a/src/server/trace/viewer/traceModel.ts
+++ b/src/server/trace/viewer/traceModel.ts
@@ -38,7 +38,8 @@ export class TraceModel {
       browserName: '',
       options: { sdkLanguage: '' },
       pages: [],
-      resources: []
+      resources: [],
+      snapshotSizes: {},
     };
   }
 
@@ -98,6 +99,8 @@ export class TraceModel {
         break;
       case 'frame-snapshot':
         this._snapshotStorage.addFrameSnapshot(event.snapshot);
+        if (event.snapshot.snapshotName && event.snapshot.isMainFrame)
+          this.contextEntry.snapshotSizes[event.snapshot.snapshotName] = event.snapshot.viewport;
         break;
     }
     if (event.type === 'action' || event.type === 'event') {
@@ -123,6 +126,14 @@ export class TraceModel {
     }
     return event;
   }
+
+  _modernize_1_to_2(event: any): any {
+    if (event.type === 'frame-snapshot' && event.snapshot.isMainFrame) {
+      // Old versions had completely wrong viewport.
+      event.snapshot.viewport = this.contextEntry.options.viewport || { width: 1280, height: 720 };
+    }
+    return event;
+  }
 }
 
 export type ContextEntry = {
@@ -132,18 +143,19 @@ export type ContextEntry = {
   options: BrowserContextOptions;
   pages: PageEntry[];
   resources: ResourceSnapshot[];
+  snapshotSizes: { [snapshotName: string]: { width: number, height: number } };
 };
 
 export type PageEntry = {
   actions: trace.ActionTraceEvent[];
   events: trace.ActionTraceEvent[];
-  objects: { [ket: string]: any };
+  objects: { [key: string]: any };
   screencastFrames: {
     sha1: string,
     timestamp: number,
     width: number,
     height: number,
-  }[]
+  }[];
 };
 
 export class PersistentSnapshotStorage extends BaseSnapshotStorage {
diff --git a/src/web/traceViewer/ui/callTab.tsx b/src/web/traceViewer/ui/callTab.tsx
index 5f0500816a..fb0fb14a19 100644
--- a/src/web/traceViewer/ui/callTab.tsx
+++ b/src/web/traceViewer/ui/callTab.tsx
@@ -39,12 +39,12 @@ export const CallTab: React.FunctionComponent<{
     <div className='call-line'>{action.metadata.apiName}</div>
     { !!paramKeys.length && <div className='call-section'>Parameters</div> }
     {
-      !!paramKeys.length && paramKeys.map(name => renderLine(action.metadata, name, params[name]))
+      !!paramKeys.length && paramKeys.map((name, index) => renderLine(action.metadata, name, params[name], 'param-' + index))
     }
     { !!action.metadata.result && <div className='call-section'>Return value</div> }
     {
-      !!action.metadata.result && Object.keys(action.metadata.result).map(name =>
-        renderLine(action.metadata, name, action.metadata.result[name])
+      !!action.metadata.result && Object.keys(action.metadata.result).map((name, index) =>
+        renderLine(action.metadata, name, action.metadata.result[name], 'result-' + index)
       )
     }
     <div className='call-section'>Log</div>
@@ -58,12 +58,12 @@ export const CallTab: React.FunctionComponent<{
   </div>;
 };
 
-function renderLine(metadata: CallMetadata, name: string, value: any) {
+function renderLine(metadata: CallMetadata, name: string, value: any, key: string) {
   const { title, type } = toString(metadata, name, value);
   let text = trimRight(title.replace(/\n/g, '↵'), 80);
   if (type === 'string')
     text = `"${text}"`;
-  return <div className='call-line'>{name}: <span className={type} title={title}>{text}</span></div>;
+  return <div key={key} className='call-line'>{name}: <span className={type} title={title}>{text}</span></div>;
 }
 
 function toString(metadata: CallMetadata, name: string, value: any): { title: string, type: string } {
diff --git a/src/web/traceViewer/ui/snapshotTab.tsx b/src/web/traceViewer/ui/snapshotTab.tsx
index 41943ed3f0..e911528a36 100644
--- a/src/web/traceViewer/ui/snapshotTab.tsx
+++ b/src/web/traceViewer/ui/snapshotTab.tsx
@@ -24,8 +24,9 @@ import { ActionTraceEvent } from '../../../server/trace/common/traceEvents';
 
 export const SnapshotTab: React.FunctionComponent<{
   action: ActionTraceEvent | undefined,
-  snapshotSize: Size,
-}> = ({ action, snapshotSize }) => {
+  snapshotSizes: { [snapshotName: string]: Size },
+  defaultSnapshotSize: Size,
+}> = ({ action, snapshotSizes, defaultSnapshotSize }) => {
   const [measure, ref] = useMeasure<HTMLDivElement>();
   const [snapshotIndex, setSnapshotIndex] = React.useState(0);
 
@@ -61,6 +62,10 @@ export const SnapshotTab: React.FunctionComponent<{
     }
   }, [action, snapshotIndex, iframeRef, snapshots]);
 
+  let snapshotSize = defaultSnapshotSize;
+  if (snapshots[snapshotIndex] && snapshots[snapshotIndex].snapshotName)
+    snapshotSize = snapshotSizes[snapshots[snapshotIndex].snapshotName] || defaultSnapshotSize;
+
   const scale = Math.min(measure.width / snapshotSize.width, measure.height / snapshotSize.height);
   const scaledSize = {
     width: snapshotSize.width * scale,
diff --git a/src/web/traceViewer/ui/workbench.tsx b/src/web/traceViewer/ui/workbench.tsx
index 46b6293f8d..69b61b9ad1 100644
--- a/src/web/traceViewer/ui/workbench.tsx
+++ b/src/web/traceViewer/ui/workbench.tsx
@@ -54,7 +54,7 @@ export const Workbench: React.FunctionComponent<{
     return actions;
   }, [context]);
 
-  const snapshotSize = context.options.viewport || { width: 1280, height: 720 };
+  const defaultSnapshotSize = context.options.viewport || { width: 1280, height: 720 };
   const boundaries = { minimum: context.startTime, maximum: context.endTime };
 
   // Leave some nice free space on the right hand side.
@@ -89,7 +89,7 @@ export const Workbench: React.FunctionComponent<{
     </div>
     <SplitView sidebarSize={300} orientation='horizontal' sidebarIsFirst={true}>
       <SplitView sidebarSize={300} orientation='horizontal'>
-        <SnapshotTab action={selectedAction} snapshotSize={snapshotSize} />
+        <SnapshotTab action={selectedAction} snapshotSizes={context.snapshotSizes} defaultSnapshotSize={defaultSnapshotSize} />
         <TabbedPane tabs={[
           { id: 'logs', title: 'Call', count: 0, render: () => <CallTab action={selectedAction} /> },
           { id: 'console', title: 'Console', count: consoleCount, render: () => <ConsoleTab action={selectedAction} /> },
@@ -124,5 +124,6 @@ const emptyContext: ContextEntry = {
     _debugName: '<empty>',
   },
   pages: [],
-  resources: []
+  resources: [],
+  snapshotSizes: {},
 };
diff --git a/tests/trace-viewer/trace-viewer.spec.ts b/tests/trace-viewer/trace-viewer.spec.ts
index b525713fd8..2615edfaaa 100644
--- a/tests/trace-viewer/trace-viewer.spec.ts
+++ b/tests/trace-viewer/trace-viewer.spec.ts
@@ -42,6 +42,9 @@ class TraceViewerPage {
     await this.page.click(`.action-title:has-text("${title}")`);
   }
 
+  async selectSnapshot(name: string) {
+    await this.page.click(`.snapshot-tab .tab-label:has-text("${name}")`);
+  }
 
   async callLines() {
     await this.page.waitForSelector('.call-line:visible');
@@ -74,6 +77,13 @@ class TraceViewerPage {
     await this.page.waitForSelector('.console-stack:visible');
     return await this.page.$$eval('.console-stack:visible', ee => ee.map(e => e.textContent));
   }
+
+  async snapshotSize() {
+    return this.page.$eval('.snapshot-container', e => {
+      const style = window.getComputedStyle(e);
+      return { width: style.width, height: style.height };
+    });
+  }
 }
 
 const test = playwrightTest.extend<{ showTraceViewer: (trace: string) => Promise<TraceViewerPage> }>({
@@ -110,6 +120,7 @@ test.beforeAll(async ({ browser, browserName }, workerInfo) => {
     page.waitForNavigation(),
     page.waitForTimeout(200).then(() => page.goto('data:text/html,<html>Hello world 2</html>'))
   ]);
+  await page.setViewportSize({ width: 500, height: 600 });
   await page.close();
   traceFile = path.join(workerInfo.project.outputDir, browserName, 'trace.zip');
   await context.tracing.stop({ path: traceFile });
@@ -129,6 +140,7 @@ test('should open simple trace viewer', async ({ showTraceViewer }) => {
     'page.click\"Click\"',
     'page.waitForNavigation',
     'page.gotodata:text/html,<html>Hello world 2</html>',
+    'page.setViewportSize',
   ]);
 });
 
@@ -166,14 +178,14 @@ test('should open console errors on click', async ({ showTraceViewer, browserNam
   test.fixme(browserName === 'firefox', 'Firefox generates stray console message for page error');
   const traceViewer = await showTraceViewer(traceFile);
   expect(await traceViewer.actionIconsText('page.evaluate')).toEqual(['2', '1']);
-  expect(await traceViewer.page.isHidden('.console-tab'));
+  expect(await traceViewer.page.isHidden('.console-tab')).toBeTruthy();
   await (await traceViewer.actionIcons('page.evaluate')).click();
-  expect(await traceViewer.page.waitForSelector('.console-tab'));
+  expect(await traceViewer.page.waitForSelector('.console-tab')).toBeTruthy();
 });
 
 test('should show params and return value', async ({ showTraceViewer, browserName }) => {
   const traceViewer = await showTraceViewer(traceFile);
-  expect(await traceViewer.selectAction('page.evaluate'));
+  await traceViewer.selectAction('page.evaluate');
   expect(await traceViewer.callLines()).toEqual([
     'page.evaluate',
     'expression: "({↵    a↵  }) => {↵    console.log(\'Info\');↵    console.warn(\'Warning\');↵    con…"',
@@ -182,3 +194,12 @@ test('should show params and return value', async ({ showTraceViewer, browserNam
     'value: "return paramA"'
   ]);
 });
+
+test('should have correct snapshot size', async ({ showTraceViewer }) => {
+  const traceViewer = await showTraceViewer(traceFile);
+  await traceViewer.selectAction('page.setViewport');
+  await traceViewer.selectSnapshot('Before');
+  expect(await traceViewer.snapshotSize()).toEqual({ width: '1280px', height: '720px' });
+  await traceViewer.selectSnapshot('After');
+  expect(await traceViewer.snapshotSize()).toEqual({ width: '500px', height: '600px' });
+});