In NR v0.19.13: Exception getting context data. See logs of the runtime.

[juggledad]

Due to a change in how flow variables are stored, this node no longer works. When you press the refresh button you get the above message in the log shows:

[contextbrowser] /contextbrowser/flow/:id TypeError: context.keys is not a function

You can follow the base reason in this thread on the forum:
https://discourse.nodered.org/t/typeerror-ctx-keys-is-not-a-function-at-exportcontextstore/2942/15