OS: Arch Linux latest
package: https://aur.archlinux.org/packages/gochiusearch
reason:
"Hiragino Kaku Gothic ProN" is not a native font for Linux.
And, mono returns Environment.OSVersion something like Unix 4.4.3.1 on Linux ( ̄□ ̄)
possible solution:
I suggest you may use generic font-family(like "Sans") let fontconfig do the job.
BTW:
Nice work (っ╹ ◡ ╹ )っ