I'm running NR in Docker and when I used the npm update from a terminal inside the container it updated just fine, as evidenced by the dashboard being at v2.22.0 above.
This is not a big problem for me but it would me more convenient if the palette manager worked fully.
I saw that announcement of the new dashboard this morning. That's what prompted me to go there to do the update. Failing that, I went with the npm command. I didn't take a screenshot before I updated and I now realize that would have been better to illustrate the issue. Trust me, it wasn't there.
Although the dashboard npm version had been updated to v2.22.0, the node-RED flow library had not been updated, and was still at v2.21.0, therefore an update was not available.
A couple of hours ago I initiated a refresh of the flow library, which updated the dashboard to v2.22.0, and was therefore then available to be updated in node-RED.