Outlook App opening a browser Tab

We got exactly the same thing, but through looking at the trigger, this time it isn't room finder in meeting creations causing the issue, but instead Microsoft have added yet another integration called "meeting insights" which relies on OWA to function - and if you have OWA turned off, opening a meeting from your calendar in which the "meeting insights" button appears will launch a web browser trying to load OWA. I wonder if this is what you're seeing too?

Unfortunately, we've not found a way to disable this at all yet. Two steps forward one step back with Outlook currently with all this infuriating OWA forced-integration rubbish.

I've highlighted the button in question below:

... changing this setting in Edge, which I never open or use, has cured it for me.

Alex_414x, do you mean you change your default browser to Edge? I tried this (with Chrome and Firefox) but it still opens the default browser (and requires a login because it doesn't recognize it). What settting are you referring to?

Sorry I thought my reply picked up the picture comment I was replying to but I now see I didn't tick the box!
It's a setting in Edge; I still use Brave as the default browser, I didn't change that.

I opened Edge and went to the settings within Edge not the PC settings:

settings/system & performance/Continue running background extensions and apps when Microsoft Edge is closed (it's near the top) - I switched this off and it worked for me. I didn't have to fiddle with the calendar or teams settings at all.

Screenshot of the reply that fixed it for me:

We got exactly the same thing, but through looking at the trigger, this time it isn't room finder in meeting creations causing the issue, but instead Microsoft have added yet another integration called "meeting insights" which relies on OWA to function - and if you have OWA turned off, opening a meeting from your calendar in which the "meeting insights" button appears will launch a web browser trying to load OWA. I wonder if this is what you're seeing too?

Unfortunately, we've not found a way to disable this at all yet. Two steps forward one step back with Outlook currently with all this infuriating OWA forced-integration rubbish.

I've highlighted the button in question below:

...

I see that button too. I just sent a test meeting to myself and now when I open it from my calendar, I get TWO of these mail tabs opening in my browser. Literally two steps back, indeed!

Sorry I thought my reply picked up the picture comment I was replying to but I now see I didn't tick the box!
It's a setting in Edge; I still use Brave as the default browser, I didn't change that.

I opened Edge and went to the settings within Edge not the PC settings:

settings/system & performance/Continue running background extensions and apps when Microsoft Edge is closed (it's near the top) - I switched this off and it worked for me. I didn't have to fiddle with the calendar or teams settings at all.

Screenshot of the reply that fixed it for me:

Thanks for clarifying and for the screenshot! Unfortunately, this doesn't work for me.