tl;dr:
There is an update coming to Google Chrome and Microsoft Edge that will cause part of ArcGIS Portal to break. You should take action by installing the patches that Esri is releasing in June to address these. If you are on 11.3, you are fine; anything earlier and you will need to either upgrade or apply a patch:
Now, the rest of the story:
Web technology moves fast; sometimes faster than we can keep up with (even the mighty Esri development team!). Coming up on July 23, 2024, Chromium (the underlying core, open-source technology that both Google Chrome and Microsoft Edge are built on) will be releasing version 127. In this version, a long-deprecated feature of JavaScript, mutation events, will be finally removed.
Mutation events were added to the HTML web standard in … well, a long time ago. They have been around in every version of Chrome, were deprecated in 2011, and had a widespread replacement in all modern browsers by 2013. At this point, there has been no excuse to use those events for nearly 11 years.
But the web moves so slowly! Even though JavaScript and TypeScript libraries move quickly and come in and out of favor seemingly as the wind changes direction, the browsers themselves are very backward compatible. They often go out of their way to make old HTML work that obeys no modern standard. We have encountered this on several projects where legacy applications (think ASP Classic) generated invalid HTML that Chrome was happy to work with, but the perimeter application firewall could not work with at all! It was good that we were forced to make those updates, but also interesting that Chrome was happy to continue with the old, non-standard, mostly invalid HTML.
This leads us to where we are today; on July 23, 2024 a new version of Chrome will fully remove support for these legacy mutation events (July 25, 2024 for Microsoft Edge). Any websites that rely on them will have errors or failures. One such website is the ArcGIS Portal homepage prior to version 11.3.
You need to deal with this very, very soon - basically immediately. If you are applying ArcGIS Patches on a monthly basis, then you will probably get it taken care of when you apply June's patches, so just be sure to apply those before July 23! If you don't apply patches monthly, here is where you stand:
If you can't get patches or upgrades done before the deadline, you still have one final hope! Enterprise Policies! Both Google Chrome and Microsoft Edge support a policy setting called "MutationEventsEnabled" that will delay the upgrade. But that only gets you about nine months, so you still have to get your updates and/or patches going ASAP.
Need help navigating this or other GIS things? Our team of certified experts can help you out. Whether that's helping with patches, upgrades, migration planning or solving those strange integration problems, dymaptic has your back!
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