Developer tool to hit /context on any event to determine it's parent state

[Half-Shot]

Is your suggestion related to a problem? Please describe.
I find myself often trying to debug which state an event depends on, because it's not always obvious by looking at the timeline over federation.

Describe the solution you'd like
An extension to the view source dialog where you can click to fetch more information about the event, like it's parents.

Describe alternatives you've considered
I've not so far.

[turt2live]

Any reason why https://github.com/Kagamihime/matrix-visualisations is insufficient for this?

related: #5327

[Half-Shot]

I guess that will do, but would be nice to have a simple "This is the state for this event" button that I can use in a pinch.