NoScript 10.1.2 no longer responsive

[jimoe]

Firefox 57.0
NoScript 101.2

Today (Sun 26-Nov) when Firefox started, NoScript was not merely disabled, it was not possible to enable it; there was no Enable button. It was fine yesterday.

I Remove'd it, re-installed it from the NoScript site. It is now in a demented state: it seems to block sites but it does not open to list anything. In fact after clicking on the "S", the icon disappeared leaving only the little box with the number of (blocked?) sites. Neither left nor right clicking induces any reaction.

What happened to noscript?