Three random Explorer examples:

https://devblogs.microsoft.com/oldnewthing/20230911-00/?p=10...

https://devblogs.microsoft.com/oldnewthing/20230324-00/?p=10...

https://devblogs.microsoft.com/oldnewthing/20220613-00/?p=10...

For code injection into applications that don't load third-party DLLs as plugins, see, e.g., Microsoft's (unsupported) toolkit for runtime API interception:

https://github.com/microsoft/Detours

You install tortoiseSVN or something similar, look at explorer.exe process or any process that use a standard "Open File" widget, and you will see some dll from the utility loaded by the process. (Easy to see with process explorer from sysinternals)