I am currently using version 3.9.0.2040 of Spire.PDF and I am having a problem with Calibri font ligature of letters "t" and "i", if they are next to each other. Attached is a sample of document preview (left side) and final PDF created by Spire (right side). You can see, that in several different fonts (Arial, Verdana, Tahoma), the letters "t" and "i" are correctly rendered. But in Calibri, letter "i" is missing (in the word "Rutina").
Can you help me solve this problem? Thank you.