Why bad text quality?

I am trying to add “Text: Rich” filter but for some reason the quality is bad. Please see the following example.

Used font is “Ubuntu Regular” and it works in other applications without problems.

What could be the problem ?

Here’s a capture of my Preview panel.
Same font, same filter.
The text looks normal to me

Your example (so others don’t have to click on that link)

I found that font in Google Fonts. I am not sure where you obtained the font.
Ubuntu - Google Fonts

Video Mode: 1920x1080, no other filters.

Exported frame:

Are you looking at the preview or an exported video? Not enough information to help further.

Thanks a lot for the replies. The bad font quality comes when I don’t maximize the MP4 video to full screen size. Fonts look sharp when maximized. I am going to dig this matter more closely in near future.

Sounds like the media player is using a fast but low-quality algorithm for scaling the video, such as bilinear. Try changing the scaling algorithm to something like bicubic and see if it makes a difference.