{"id":14937,"date":"2026-02-12T09:02:18","date_gmt":"2026-02-12T00:02:18","guid":{"rendered":"https:\/\/m365jp.net\/?p=14937"},"modified":"2026-02-12T09:06:07","modified_gmt":"2026-02-12T00:06:07","slug":"mc1230888-teams-on-the-web-browser-update-required-by-may-15-2026","status":"publish","type":"post","link":"https:\/\/m365jp.net\/index.php\/2026-02-12-mc1230888-teams-on-the-web-browser-update-required-by-may-15-2026","title":{"rendered":"MC1230888 | Teams on the web \u2013 Browser Update Required by May 15, 2026"},"content":{"rendered":"
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MC1230888 | Teams on the web \u2013 Browser Update Required by May 15, 2026<\/th>\n<\/tr>\n<\/tbody>\n<\/table>\n
\n\n\n\n\n\n\n\n
Classification<\/th>\nplanForChange<\/td>\n<\/tr>\n
Last Updated<\/th>\n02\/11\/2026 23:14:31<\/td>\n<\/tr>\n
Start Time<\/th>\n02\/11\/2026 23:14:05<\/td>\n<\/tr>\n
End Time<\/th>\n06\/17\/2026 07:00:00<\/td>\n<\/tr>\n
Message Content<\/th>\n\n

Introduction<\/b><\/p>\n

<\/p>\n

To maintain security, performance, and long-term compatibility, Microsoft Teams on the web will require modern browser standards. Beginning May 15, 2026<\/b>, Teams on the web will only be supported on browsers that are compliant with ECMAScript 2022 (ES2022)<\/b>.<\/p>\n

When this will happen<\/b><\/p>\n

<\/p>\n

    <\/p>\n
  • Now through May 14, 2026:<\/b> Users on unsupported browsers will see reminder banners.<\/li>\n

    <\/p>\n

  • Beginning May 15, 2026:<\/b> Teams on the web will be blocked on non-compliant browsers.<\/li>\n

    <\/ul>\n

    How this affects your organization<\/b><\/p>\n

    <\/p>\n

    Who is affected:<\/b><\/p>\n

    <\/p>\n

      <\/p>\n
    • All tenants using Teams on the web<\/b><\/li>\n

      <\/p>\n

    • Users accessing Teams through unsupported browser versions<\/b><\/li>\n
    • IT administrators responsible for browser standards and endpoint management<\/li>\n<\/ul>\n

      What will happen:<\/b><\/p>\n

      <\/p>\n

        <\/p>\n
      • Reminder banners will appear before enforcement.<\/li>\n

        <\/p>\n

      • Blocking page will appear starting May 15, 2026<\/b> until the browser is updated.<\/li>\n

        <\/p>\n

      • The change is enabled by default<\/b> and cannot be disabled.<\/li>\n
      • Desktop and mobile Teams clients are not impacted<\/b>.<\/li>\n<\/ul>\n

        What you can do to prepare<\/b><\/p>\n

        <\/p>\n

          <\/p>\n
        • Inventory browser versions used to access Microsoft 365 web apps.<\/li>\n

          <\/p>\n

        • Ensure users are on supported browsers and versions<\/b>.<\/li>\n

          <\/p>\n

        • Notify helpdesk staff and end users ahead of enforcement.<\/li>\n<\/ul>\n

          Browser compatibility guidance<\/b><\/p>\n

          All currently supported versions of Microsoft Edge, Google Chrome, Mozilla Firefox, and Safari are ECMAScript 2022 (ES2022)<\/b> compliant. Browsers that are out of vendor support should be assumed non\u2011compliant. A browser is considered \u201cout of vendor support\u201d when its publisher no longer provides updates or security fixes; these browsers should be assumed unsupported for Teams on the web.<\/p>\n

            <\/ul>\n

            Compliance considerations<\/b><\/p>\n

            <\/p>\n

            Conditional Access policies may be impacted if users attempt access with unsupported browsers.<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

            MC1230888 | Teams on the web \u2013 Browser Update Required by May 15, 2026 Classification planForChange Last Updat […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-14937","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts\/14937","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/comments?post=14937"}],"version-history":[{"count":0,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts\/14937\/revisions"}],"wp:attachment":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/media?parent=14937"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/categories?post=14937"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/tags?post=14937"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}