DBMS Output - text display corruption on long lines

Toad for Oracle Base Edition (32-bit)
Windows 11 Business, Version 21H2

I get corrupted display on DBMS Output tab if the line is too long and exceeds the width of the control. Moving over the line or highlighting parts of the line cause gaps to dynamically appear in text and jump around.

Font is Courier New, Regular, 7pt.

Hi Paul,

I tried to reproduce it with this block of code but it looks ok to me. How does it look for you?

  i number;
  j number;
  s varchar2(4000);
  s := null;
  j := 0;
  i := 0;
  while i < 1000 loop
    i := i + 1;
    s := s || to_char(i);
    if length(s) > 20 then
      j := j + 1;
      if j > 20 then
        dbms_output.put_line('group' || to_char(j) || ' = ' || s || ', ');
        j := 1;
        dbms_output.put('group' || to_char(j) || ' = ' || s || ', ');
      end if;
      s := null;
     end if;
  end loop;

Hi John

Yes, I get the problem. Clicked in the DBMS_Output edit box:

FWiW, I cannot reproduce this effect either, using Dorlon's code, although I'm running 64-bit Toad... could this be a 32-bit issue?

I can reproduce it on a scaled display.