In the past, Vietnamese fonts were split between different encodings like TCVN3 (ABC) or VNI. If you didn't have the exact right font installed, your text would look like a string of squares or gibberish.
The suffix stands for Updated . This version usually includes: tai font vn unishx upd
Here is a deep dive into what this keyword represents and how to get these fonts working for your projects. What is the VN Unishx UPD Font? In the past, Vietnamese fonts were split between