The font display in the button is incorrect

[Ppsoft1991]

I created a button and set the style, but the font not in the center

btn.getStyleClass().setAll("btn", "btn-sx", "btn-primary");

jdk version 11
implementation('org.kordamp.bootstrapfx:bootstrapfx-core:0.4.0')

[Dante12129]

I am seeing this as well