Not either of the Gerygonies, bill and head shape not correct. Ryu, I guess you are saying Weebill because of bill sie but I am not so sure. Where is the pale eye? Could be angle of photo. Having said that I am not confident that I can id this image. Chris
Right colour, short stubby bill, faint pale brow. The eye is cast in shadow. I'm fairly confident since I've done a lot of IDing small birds from my own poor images in the past. Since you are happy to rule out Gerygones and its beak is not any Thornbill which really leaves no other real possibilities, I will confirm it.