create field suddenly not a good chunk

[Matt Maier]

As far as I know I didn't make any changes that would explain this.

All of a sudden this line: "create field stack "HowstrBeta"  is giving me
this error "(Chunk: source is not a container), char 1"

After some experimentation and googling I discovered that it would work
again if I changed that line to this: "create field (the long ID of stack
"HowstrBeta").

BTW, it was the same error for two other areas which created graphics
instead of fields.

Any ideas why Livecode would happily take "create field stack "Whatever""
for many months and then suddenly demand it be phrased differently?