Site compatibility-impacting changes coming to Microsoft Edge
This article lists the schedule of changes for Microsoft Edge and the Chromium project. It also highlights any differences and high-impact changes which the Microsoft Edge team is tracking especially closely.
For functionality and compatibility reasons, Microsoft Edge adopts nearly all of the Chromium project's changes to the web platform. However, Microsoft retains full control of the Microsoft Edge browser and may defer or reject changes. The Microsoft Edge team decides if the change benefits browser users.
For information about upcoming Chromium project web platform changes, see Chrome Platform Status Release timeline.
Check this article often as the Microsoft Edge team updates this article as thinking evolves, timelines solidify, and new changes are announced.
Differences from the Chromium schedule, and high-impact changes
This table lists:
- Changes where the rollout schedule for Microsoft Edge differs from the upstream Chromium project.
- High-impact changes which the Microsoft Edge team is tracking closely.
|Deprecate unload event
|Future release (TBD)
|Introduces a new Permission-Policy to allow creating unload event listeners. The default policy is
allow, but the default policy will gradually be migrated to
deny, such that unload handlers stop firing on pages, unless a page explicitly opts in to re-enable them. This change is happening in the Chromium project, on which Microsoft Edge is based. For more information, see Intent to Deprecate: Deprecate unload event.
|Future release (TBD)
window.confirm from cross-origin iframes. This change is happening in the Chromium project, on which Microsoft Edge is based. For more information, see Intent to Remove: Cross origin subframe JS Dialogs.
|Removal of mutation events
|Removes support for mutation events in Chromium. Use the MutationObserver API instead. See Intent to Deprecate: Mutation Events.
|Added support for AVIF and AV1 file formats
|Microsoft Edge now supports the AVIF and AV1 file formats, which offer better compression and higher quality images and videos. Users can enjoy faster loading times and better quality media on websites.
|Ignore modifications to
document.domain by default
document.domain property historically could be set to relax the same-origin policy and allow subdomains from a site to interact. This behavior will be disabled by default such that setting the
document.domain property will have no effect. For more information and workarounds, see Microsoft Edge will disable modifying document.domain.
|New TLS server certificate verifier
|v111 (managed devices), v109 (unmanaged devices)
|No site compatibility impacts are anticipated. If you have uncommon TLS server certificate deployments, you should test in v109 to confirm there's no impact. For more information and testing guidance, see Changes to Microsoft Edge browser TLS server certificate verification.
Notation for browser versions
This article uses the following notation for browser release numbers.
|The feature or change ships in Microsoft Edge version 123.
|The feature or change ships in Microsoft Edge version 123, which is one release after the feature or change ships in Chrome version 122.
|The feature or change ships in Microsoft Edge version 123, which is two releases after the feature or change ships in Chrome version 121.
|The feature or change ships in version 123 of the Beta preview channel of Microsoft Edge.
|The feature or change ships in version 123 of the Dev preview channel of Microsoft Edge.
|The feature or change ships in version 123 of the Canary preview channel of Microsoft Edge.