diff --git a/app/server/lib/sendAppPage.ts b/app/server/lib/sendAppPage.ts
index 314486c0..95c38282 100644
--- a/app/server/lib/sendAppPage.ts
+++ b/app/server/lib/sendAppPage.ts
@@ -297,8 +297,11 @@ function getPageMetadataHtmlSnippet(req: express.Request, config: GristLoadConfi
 
   const icon = maybeDoc?.options?.icon ?? new URL('icons/grist.png', staticBaseUrl).href;
   const escapedIcon = handlebars.Utils.escapeExpression(icon);
+  const iconSize = '100';
   metadataElements.push(`<meta name="thumbnail" content="${escapedIcon}">`);
   metadataElements.push(`<meta property="og:image" content="${escapedIcon}">`);
+  metadataElements.push(`<meta property="og:image:width" content="${iconSize}">`);
+  metadataElements.push(`<meta property="og:image:height" content="${iconSize}">`);
   metadataElements.push(`<meta name="twitter:image" content="${escapedIcon}">`);
 
   const title = (getPageTitle(config) ?? translate(req, 'Welcome')) + getPageTitleSuffix(config);