I'm noticing that if I place a transparency mask on a freeform gardient object, the gradient drops a bunch of nodes. If I try to work around it by moving the existing nodes they start dissapearing. This was happening in AI 2021 so I upgraded to 2022 and the problem persists. Makes it unusable for this purpose.
Here's a video that shows all the nodes I started with and how many I ended up with after making the mask.