Add hack
From Akuli/porcupine:
# TODO: the next 3 lines are a hack?
# If they are really needed, why it isn't in sv-ttk by default?
main_window.option_add("*Text.highlightThickness", "0")
main_window.option_add("*Text.borderWidth", "2")
main_window.option_add("*Text.relief", "solid")
Add hack means add them to the sv_ttk as default?
Yeah, though I'm not sure, if it makes sense to make them the default.
Hightlightthickness is 0 means the Text widget will not show the highlight border and I agree this, because the border looks ugly.
And here is a screenshot that shows the difference between borderwidth=2 and the normal borderwidth, there are 1px black frame in the left and 2px grey frame in the bottom, so I disagree the second.
And the relief, here is the screenshot (test with borderwidth=2):
I think normal relief is better than the solid, so I think they can set the solid by themself.
So we just need set the highlightthickness=0 as default.
(Of course this is just my option, maybe we can ask Akuli for options.)