I’m confused…
Right now this does not look like you are taking advantage of most of the benefits of the HTML printer - notably non-monospace fonts.
Take a closer look at HTML of better yet “Document Printer” formatted ticket templates which should give you greater control over character formatting.
In my ticket template I don’t use <L><C><T><F> style commands (which I think work best in a monospace and ESC/POS environment.
For horizonal lines I use borders of tags in XAML Document format.
As @markjw pointed out in this post, HTML format isn’t really a thing… In reality, SambaPOS is taking a bunch of HTML looking tags and converting them as well as it can in to XAML FlowDocument (XPS) format, which is what is actually used to generate the output to send to the printer driver. By writing the template directly in XAML you will have the greatest level of control over the output.
Try using the following to get started and see if this XAML approach might work for you…
[LAYOUT]
<Section FontFamily="Calibri" FontSize="12" Margin="0" Padding="0" LineHeight="1" TextAlignment="Left">
<Section>
<Paragraph FontSize="30" TextAlignment="Center"><Bold>myShop</Bold></Paragraph>
</Section>
<Section BorderThickness="0,2,0,2" BorderBrush="Black" Padding="0,3,0,3">
<Paragraph>This section has a border top and bottom</Paragraph>
</Section>
<Section>
<Paragraph FontSize="15" Margin="0,0,0,15">Size 15 text. How long will this run until it starts to wrap on to the next line?</Paragraph>
<Paragraph FontSize="20" Margin="0,0,0,15">Size 20 text. How long will this run until it starts to wrap on to the next line?</Paragraph>
<Paragraph FontSize="25" Margin="0,0,0,15">Size 25 text. How long will this run until it starts to wrap on to the next line?</Paragraph>
<Paragraph FontSize="30" Margin="0,0,0,15">Size 30 text. How long will this run until it starts to wrap on to the next line?</Paragraph>
</Section>
</Section>
For me, this gives the following output…
