Contents lists of containers don't work any more

This used to compile just fine (2 years back), now it doesn’t. I’m having problems with other container contents lists. Has something changed?

The playstaircase is in the playroom. it is scenery and a supporter. “A series of tall steps, which form a sort of right triangle pyramid ending just below the ceiling of the room. Each stair is quite tall[if wobblytime is happening]; daunting, given your current state[end if]. At the top, [the contents of the playstaircase], can be seen peeking over the edge.”.

Here’s the error I see:

Problem. In the line ‘“A series of tall steps, which form […] can be seen peeking over the edge.”’ , I was expecting that ‘list the contents of the playstaircase’ would be something to ‘say’, but it didn’t look like any form of ‘say’ that I know. So I tried to read ‘list the contents of the playstaircase’ as a value of some kind (because it’s legal to say values), but couldn’t make sense of it that way either.
Sometimes this happens because punctuation has gone wrong - for instance, if you’ve omitted a semicolon or full stop at the end of the ‘say’ phrase.

The “[contents of something]” syntax was abolished in build 6L02 (in 2014). There are always alternative expressions available. Here you can just replace it with “[a list of things on the playstaircase]”.

Ah! Thank you!