While polishing my newly created Fusion Invoice Template, I wanted to decrease the page margins by half to accommodate more of my terms in a single page. After figuring out the library (MPDF) being used for generating PDFs from HTML, I found the helper responsible for creating the actual PDFs from within the application.
The helper file can be located at /application/helpers/mpdf_helper.php
In there, at about line # 24, comment out the following line of code:
$mpdf = new mPDF();
And add the following line of code above or below the commented line:
$mpdf=new mPDF('','', 0, '', 15, 15, 16, 16, 9, 9, 'P');
Which will set margin to its default values:
All values should be specified as LENGTH in millimetres.
If you are creating a DOUBLE-SIDED document, the margin values specified will be used for ODD pages; left and right margins will be mirrored for EVEN pages.