Exporting jpg/bmp lose lineweights...

Hi,
I am a new user, I have used AutoCAD for 20 years but am completely new to LibreCAD.
I am having an issue, when I try and export from the print preview view(I want black and white, if there's another way to do this I would be interested) to a jpg or bmp format I am losing all the line weights. If I export from the same place to pdf format the line weights are correct.
What am I missing? Cheers

Sadly, I have to confirm this. As a workaround you may convert the pdf to an image format or use a printing app like PDFCreator, where you can also print to an image format with a settable resolution.

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