I think that happens when you launch Teams from Start. But that Teams icon is actually the link to the Old Teams with the New Teams having its own also new but separate icon somewhere else in the Start menu...

Because Microsoft.

OMG. Using it for RegEx searches! How had that not even crossed my mind?

I've tried learning RegEx basics and using some websites to point me in the right direction when a specific use comes up, but tuning the search string correctly usually takes longer than it's been worth. Off to ChatGPT it is!

I have found myself using Feedly more these past few weeks as well.

If you're on Android, a great companion is the FeedMe app. It has a lot more customization options and can download (for offline reading) full articles, rather than just showing the snippet Feedly does.