Hi Doug,
Thanks for your email and welcome to the community.
There is a Uservoice open here for exactly this
https://microsoftteams.uservoice.com/forums/555103-public/suggestions/18681580-acknowledge-exception...
And here specifically for Firefox
https://microsoftteams.uservoice.com/forums/555103-public/suggestions/33979882-support-for-firefox-f...
I voted! Would recommend you vote and draw as many people to this as possible to get it in front of Microsoft. I will also raise it at the Teams AMA next Wednesday and relay it back to Team so it has their attention.
I hope that I answered your question. If I have please like the post and mark it as the solution. I look forward to more of your questions in the future. Thanks again for reaching out.
Best, Chris