Asanka and I did some tests creating Unicode Sinhala PDF documents and
then copying 'n' pasting the content into a text file on GNU/Linux
(using Open Office) and Windows (using Adobe Acrobat Writer). Both
platforms had problems doing this. The most common cases were missing or
additional dependent vowels.
We recommend that you do NOT copy 'n' paste Unicode Sinhala text from
PDF documents unless you are willing to proof-read.