mPDF >= 4.3 produces PDF files which are specified as version
1.4 is the lowest specification which contains all the features used in mPDF - with a few minor exceptions:
- SetDisplayPreferences($preferences) allows the option to include
- Using $mirrorMargins, mPDF will set by default
Subjectfield of Annotations (PDF-1.5)
mPDF < 2.0 produced PDF files which were specified as version 1.3 (the file starts with
mPDF >= 2.0 was changed to specify
%PDF-1.5, to allow for changes needed using Annotations.