Well, Plaits has been released so no need to discuss it here any further. However, in a video on Plaits by erstlaub (David Fyans), we can clearly see the right-hand edge of another new, unreleased Mutable module:
It is clearly an envelope generator, with LED slider pots for the duration of each segment - the LED in the slider seems to light while that segment is active. There would appear to be input jacks suggesting that external CV control is possible. Note also the output jack that is visible, labelled “6” (in Sanskrit/Marathi/Devanagri script). Is this a six channel envelope generator? Or is that a trigger output for segment 6 of the envelope?
Also buttons and multi-colour LEDs above each segment slider - to set the segment shape?
My guess is that this is Cascades, a chained envelope generator, possible with 6 envelopes that can be chained into more complex envelopes, or used separately.