Application of Legendre Filter

Do you know any actual application of Legendre filter ?

https://en.wikipedia.org/wiki/Optimum_%22L%22_filter
http://mathscinotes.com/2011/06/the-...imum-l-filter/

I compared filter characteristics of the followings.

Butterworth : order=3, ω_p=1.0, A_p=3dB
Chebyshev Type I(Passband Ripple) : order=3, ω_p=1.0, A_p=3dB
Chebyshev Type II(Stopband Ripple) : order=3, ω_p=1.0, A_p=3dB, ω_s=1.8
Legendre : order=3, ω_p=1.0, A_p=3dB

Also I attached a figure which shows order dependency of Legendre Filter.

I don't think Legendre filter has distict advantage.
I think this shows a reason why Legendre filter is unpopular.