LB5.353 Windows 10 32 bit chr$(9) in mainwin

[tsh73]

for i = 1 to 5
   a$=left$("12345",i)
   print a$;chr$(9);a$;chr$(9);a$;chr$(9);a$;chr$(9)
next
Expected result:
strings delimited by TAB
What happened:
it is indeed delimited by TAB, you can see if after copying/pasting to Notepad++ or Excel

But in LB5 mainwin it doesn't look like it is delimited at all for i = 3

(well, in LB4 it did not looked delimited at all, while after copy/paste all TABS are there)