Clean-up inactive m-lines

[skmax]

Hi all

I'm using the media server for the group video calls and due to the nature of the app one participant can be in the call for a long period of time, but other participants join from time to time. Since we need to add new m-lines for each newly joined participant's stream and make m-lines inactive when tracks are removed, the SDP of long-stay participants grows over time to quite a big size. I use unified plan by SDPManagerUnified.js from the lib

As we can't remove m-lines, wouldn't make sense to at least clean up inactive m-lines by removing unneeded attributes (ssrcs, ext, candidates, etc) from them? Please, let me know what you think.

Thanks