Strange upload performance when using firefox

We run our own jitsi-server and we encounter a strange problem when using firefox: Firefox consumes much more upload-bandwith than chrome, it is almost impossible to use firefox without dropping the connection. Latest firefox and chrome were used.
If we switch back to google-chrome, everything seems fine.

Here the strange uploads with firefox:

Today I also tested with the server. Here, I can not reproduce this strange firefox-behaviour. What is wrong with our jitsi-server and firefox?

Which version of jitsi-meet do you use? In latest versions we added simulcast to Firefox which greatly reduces the bandwidth of server upload when there is a FF participant in a meeting.

Hello, here is the console debug output filtered to “version”:

2020-05-17T10:19:16.515Z [modules/version/ComponentsVersions.js] <s.prototype.processVersions/<>: Got xmpp version: Prosody(0.11.2,Linux) Logger.js:154:22

2020-05-17T10:19:16.518Z [modules/version/ComponentsVersions.js] <s.prototype.processVersions/<>: Got focus version: JiCoFo(1.0.567,Linux) Logger.js:154:22

2020-05-17T10:19:17.576Z [modules/version/ComponentsVersions.js] <s.prototype.processVersions/<>: Got videobridge version: 2.1.197-g38256192

What is the Firefox version you saw the problem with?

Tested today with 76.0.1, 64bit, windows10
Tested yesterday also with previous version 75, 64bit
Both show the same issues: upload graphs look like heartbeat-diagrams with up to 4.9Mbit peaks (why does it consume so much?) which cause a very unstable video experience.