Some large companies put installation restrictions on third-party software for security reasons, and find that throwing money at Microsoft for an enterprise support contract is cheaper than re-engineering their ancient internal software to work on something other than IE.

And because these are also the types of giant companies that tend to shit money, there are plenty of mid-sized B2B saas companies willing to bend over backwards to win a contract and earn their droppings.

So I'm sure there are a good few developers forced to support IE11 by a bad contract who will be bummed by this news.

But full deprecation has to happen eventually, and it will only help the effort to have engineers telling middle management "the project will take twice as long because we have to support IE11".

The C# app is built using WebBrowser Control[1] which is tightly integrated with the app itself. WebBrowser only supports IE11 but the webapps that it connects to are increasingly dropping support.

The vendor is reluctant to upgrade their app because the replacement options apparently (?) require extensive refactoring to get the same integration.

IE11 seems to be in a weird limbo. But the fact that it's still technically supported by Microsoft means that conservative software vendors aren't forced to migrate.

[1] https://docs.microsoft.com/en-us/dotnet/desktop/winforms/con...

Yeah, it's practically gone from the public web. But when you look at business stuff, there is a lot more IE out there still than people realize.