What do you think about naming thisblocked()? I like to use context manager names that are not imperative verbs and cannot be confused with simple functions. There is no general convention on this in the community, but I thinkwith callbacks.blocked() reads quite nicely.

@timhoffm, apparently there is a preferred convention and your suggestion lines up with that :)
https://www.python.org/dev/peps/pep-0343/#examples
I changed toblocked and moved the change note over to "next what's new" and included a short example there.

So is maybe annoying, but I think this needs a short API changes note too. only incompatible changes need API change notes.

Also, and I might be confused about the functionality here, but would it be possible for the what's new example to be slight less toy/use like one of the auto registrated callbacks or something?

I came up with another toy-like example, but with interactivity on the figure canvas and disabling key-press events. Did you have another example/area in mind to apply this? It looks like the widgets keep their callbacks private in_observers, so I guess this doesn't really help the end user currently over there.

Using fig.canvas.callbacks is perfect - I was unsure whether the functionality extended to the fig callbacks and this clears it right up & I think would be a common use case 😄