<PRE> in textEdit does not use fixed size font on Android

I have a textEdit as part of a layout in my QMainWindow.

I call the following (extracted, minimized example, real lines are longer, no real data in example):

ui->textEdit->setHtml("<PRE>\n00 00000000\n00 1111----\n ----1111\n</PRE>\n");

I assumed to get ("correct")

00 00000000
00 1111----
----1111

(all lines end at same position, looks correct, at least on my system, here in bug tracker).

But I get ("wrong", not real amount of characters, but it looks like this)

00 00000000
00 1111-- (each '-' is smaller, not fixed size)
-1111 (each space and '' is smaller, not fixed size)

It is correctly displayed on Windows, but wrong on Android (Nexus 7 (2012)).
It looks like implementation on Android does not use fixed size font.

I already tried additionally to set font of textEdit, e.g. by

ui->textEdit->setStyleSheet("font: 9pt \"Courier\";");

or

QFont font("Monospace");
font.setStyleHint(QFont::TypeWriter);
ui->textEdit->setFont(font);

It sometimes changes font or font size, but never looked to be a fixed size font on Android.

I get the complete output as string from a big (already existing) subroutine,
so it would be no solution to use something like a HTML table for each character,
at least I think this is no acceptable solution to do this.

I also tried <TT> or <CODE> without success.

Any other idea?