I actually set it up like this - here's why

The WebCodecs encoder that Color.io uses to encode videos is currently unable to compress grain in a way that yields somewhat manageable file sizes. Grain is inherently hard to compress because of the randomness it introduces both spatially and temporally.

I wish I didn't have to do this but I haven't found a way to encode and compress grainy video that doesn't create absurdly huge files. I'm currently using the avc1.4d0034 (Main 5.2) codec variant for encoding because that seems to be the most consistently supported codec across the devices I've tested on.

If anyone has insights into what codec variants might be better suited for compressing grainy footage while also preserving the structural integrity of the grain (aren't these fundamentally at odds?!) please share!

@tomr I've just changed the default behaviour for desktop browsers so that the grain no longer resets. The file size issue mentioned in my previous comment only seems to affect iOS Safari for which the grain density will continue to be reduced to prevent excessive file sizes that cause memory overflow.