Why does urxvt display this box drawing glyph differently?

I’m switching to urxvt and noticed something on the way. I use zsh and powerlevel10k with it. The powerline, if that’s what it’s called, is being differently on urxvt, even though both konsole and urxvt are using the same font, Meslo LGS NF.
Below are the screenshots of the glyhp, the leftmost one:
urxvt:

konsole:

These are the glyphs: ╭─ (U+256D) and ╰ (U+2570).

As you can see, konsole display are straight bar but urxvt shows it as curved. How can I fix this? And more importantly, what’s causing this?

My config:

! Set depth to make transparency work.
URxvt*depth: 32

! Custom urxvt settings.
URxvt.scrollBar:    false
URxvt.font:         xft:MesloLGS NF:size=13:antialias=true
URxvt.boldFont:
URxvt*letterSpace:  -2