&webpmode has been modified a bit. Main change is that you now enable it by add
&webpto the sender's URL, and
&codec=webpto the viewer's URL (otherwise, it falls back to normal video mode). No need for
&broadcastanymore. (as a reminder, this mode sends the video as a series of low-quality images, rather than a more efficient video stream).
&chunkedmode is replacing its purpose there, but you might still want to use this mode when the viewer-side does not support video playback or hardware acceleration. Specifically, this option lets you bring motion images (aka, crude video) into the streamlabs mobile app, as a browser source, where other forms of video decoding is not supported.