try

This seems to be both .NET and in the browser, so my first thought was "is this a Blazor (1) issue?" i.e. for .NET targeting WASM in the browser. It could be, Blazor dates back to 2018 and this bug is from 2019, this is the kind of thing that happens in the early days. The parent repo name and readme is more informative as to the scope, and confirms that somewhat: https://github.com/dotnet/try > Welcome to the Try .NET repo. ... Online, powered by Blazor, Users can run and edit code all in the browser. It's an amusing bug, but not a current or widespread issue. 1) https://en.wikipedia.org/wiki/Blazor

Thanks, fixing that here: https://github.com/dotnet/try/pull/638

I agree with https://github.com/dotnet/try/issues/290#issuecomment-503768... - this seems pretty likely to be "you are using `print(...)` but don't have a custom one in scope, so it's calling the window's func" It happens in Firefox too, fwiw. Probably just a mono.js flaw.