Widget for displaying kernel busy

I don’t know of amything that monitors the kernel per se; however, you can make status displays to provide feedback to users various ways. Some examples are pointed to in this post and also this Volia example has some. (Repo for that example is here.) There’s a progress bar widget example here. (Presently, that last one doesn’t run in Voila in launches from that repo because environment no longer includes Voila; however, it had originally been developed using Voila, see here. And I just copied the content into a session where Voila works the progress bar kicks off. Although I didn’t have one of the complex dependencies installed, and so it didn’t complete without an error.)