Solved
Edit Scripting Screen Menu won't expand
Recently when attempting to add a script token, the right hand menu of standard and custom objects won't expand. How do we fix this? See screenshot.

Recently when attempting to add a script token, the right hand menu of standard and custom objects won't expand. How do we fix this? See screenshot.

Unfortunately not uncommon and a frustration indeed. Just raised this with the product team to see if the bug can be fixed. In the mean time, any of the solutions the guys suggested will generally do the trick.
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