Hi
It works for me.
I'm able to test two way video chat between Chrome 59 (59.0.3071.115) and Firefox 54 (54.0.1).
Video Chat sample (in fact it is two-way conference):
https://wcs5-eu.flashphoner.com/demo2/video-chat
If you test on the same PC, make sure you have two web cams (for example USB webcam + built-in webcam).
Because you can't use the same cam in Chrome and Firefox, it will be a conflict and you won't be able to join to the room if your cam is already in use in other browser.
Could you provide versions of your browsers and a screenshot?
Could you test with two different cams or from two different PCs, or using a cam splitter like Manycam.