Microsoft have changed the icons for Office. The new ones are aesthetically unpleasing and make it hard to find the Office Application in the taskbar.

You can see the icons here.

https://news.microsoft.com/europe/2018/11/29/say-hello-to-microsofts-new-office-icons/

I'm starting a petition to try and persuade Microsoft to change back to the good old icons that have remained largely the same since 2013.