What is the ruling on hair highlights (mesh), and is it considered one of the types of heavy dyes that prevent water from reaching the skin and invalidate ablution?

Dye that does not have a tangible mass and remains on the hair and body, and does not prevent water from reaching the limbs during ablution, does not affect ablution; it is like henna. As for dye that retains a tangible, solidified mass on the hair or body, whatever remains of it must be removed.