I have this using Firefox on a 2019 Macbook Pro with 16GB RAM.

If the laptop has not been restarted for a while, Firefox tabs will eat up more and more memory over time until it makes the mac kind-of unresponsive (*) and will need to get hard power cycled.

The only signs that this is about to happen are two:

1. Any audio-emitting webapp will start to get very choppy, whether is youtube on FF, Google meet on chrome, or a slack call/huddle. Which is the problem I think you are referring to.

2. Switching workspaces animation will get very very choppy. Usually when this happens it's already almost too late.

(*) this means that while the pointer is still moving smoothily, even from a BT mouse, there is no reaction to any click or keyboard typing.