Won't preview files of 1 byte(1 character)

[dabenlee]

It won't preview files of 1 byte(1 character), and it works after I append another character into it (2 characters).
Then I try this even though I don't know if it is valid:

defaults write com.whomwah.quicklookstephen minFileSize 1

and it doesn't make any difference.

Btw, the system built-in text ql plugin's preview on a ".txt" file doesn't have this problem.

QuickLookStephen latest, macOS Big Sur 11.2.3