Textmaker doesn't switch to italic font for Cyrillic texts

[NX-01]

In principle I don't use italic versions of fonts for my personal documents but lawyers and legal services do use it and that's how I noticed that the "I" button doesn't work properly. I could write a long explanation about the problem but I think visual explanation works the best, so here's one. Also note that this problem only occurs with Cyrillic alphabet. Latin works fine.

https://www.mediafire.com/file/4digqk2p ... m.mkv/file
(the video is raw format, meaning that I haven't converted it. It was recorded using simplescreenrecorder, so if it doesn't run for you, you'll have to convert it using whatever codec you have installed)

As a workaround for this problem I had to find and download a font named "times new roman italic.ttf" and select that font when I want the text to be italic. I have all MS fonts installed and MS Office (ran with Wine 10.5) properly turns "Times New Roman" into italic when the button for italic is pressed (without selecting the workaround font). Only FreeOffice doesn't do that. That makes me believe the problem is in FO, not in the fonts themselves.
The video also shows that the workaround works but not the traditional way.
FO is installed from AUR but the source trizen uses to install it is from your website: http://www.softmaker.net/down/softmaker ... -amd64.tgz