Missing native special characters in QTextBrowser

[michelson]

Hello,

I have a problem with getting accented characters right in QTextBrowser. I connect signal which sends QString and slot which appends it to QTextBrowser like that:

emit errorString_changed(tr(qPrintable(QString("Pobrano wersję firmware'u: %1").arg(QString::fromLocal8Bit(frmw)))));
//frmw is QByteArray which I receive from a device

connect(rej, SIGNAL(errorString_changed(QString)), ui->logTextBrowser, SLOT(append(QString)));

The letter "ę" is printed as a square with small question mark if you know what I mean.
I guess this is come kind of codec thing, but never worked woth those. I didnt find any QTextBrowser::setCodec() or something similar. How can I fix this?