the xml was improperly formatted (past Chr(4))

Hi
How to assign to string char #4?

Dim s as String
s=Chr(0) 'OK, value of s is #0
s=Chr(4) 'the xml was improperly formatted
s=s&"some text" 'the xml was improperly formatted

It worked properly one month ago.

Any idea?
B2A ver. 1.70 (Core 1.67)

Hi.
The problem applies to the debugger only. Fortunately, it saves in files correctly as File.WriteString(). Sorry for the confusion