I was experiencing an error locally that also shows up in the playground: Babylon.js Playground
When you go to “Rendering Pipeline” > “lens”, the right panel disappears and I get those 2 errors in my console:
babylon.inspector.bundle.js:51 TypeError: Cannot read property 'toString' of undefined
at t.render (babylon.inspector.bundle.js:31)
at so (babylon.inspector.bundle.js:51)
at lo (babylon.inspector.bundle.js:51)
at ho (babylon.inspector.bundle.js:51)
at Xo (babylon.inspector.bundle.js:51)
at Ko (babylon.inspector.bundle.js:51)
at Li (babylon.inspector.bundle.js:51)
at _i (babylon.inspector.bundle.js:51)
at Di (babylon.inspector.bundle.js:51)
at wn (babylon.inspector.bundle.js:51)
yo @ babylon.inspector.bundle.js:51
n.callback @ babylon.inspector.bundle.js:51
ua @ babylon.inspector.bundle.js:51
ca @ babylon.inspector.bundle.js:51
Ri @ babylon.inspector.bundle.js:51
Li @ babylon.inspector.bundle.js:51
_i @ babylon.inspector.bundle.js:51
Di @ babylon.inspector.bundle.js:51
wn @ babylon.inspector.bundle.js:51
babylon.inspector.bundle.js:31 Uncaught TypeError: Cannot read property 'toString' of undefined
at t.render (babylon.inspector.bundle.js:31)
at so (babylon.inspector.bundle.js:51)
at lo (babylon.inspector.bundle.js:51)
at ho (babylon.inspector.bundle.js:51)
at Xo (babylon.inspector.bundle.js:51)
at Ko (babylon.inspector.bundle.js:51)
at Li (babylon.inspector.bundle.js:51)
at _i (babylon.inspector.bundle.js:51)
at Di (babylon.inspector.bundle.js:51)
at wn (babylon.inspector.bundle.js:51)
Tested on Windows 10, Chrome Version 72.0.3626.109 (Official Build) (64-bit)