Opacity with line 2d and anti-aliasing on causes sprite debug boxes to appear

Created by: EricEzaM

Not sure if this is as it supposed to be or not... But might as well try submit a bug to see if it is one.

Godot version: 3.2 stable OS/device including version: Windows 10 1903 Issue description: Line 2d shows debug boxes when anti-aliasing is enabled and material is translucent (i.e. 0 < alpha < 1). Example below

Steps to reproduce: New project Add Line2d Add some points Set default color alpha to be <1, e.g. 0.5 Make width larger (to better see effect), e.g. 30 - 50 Enable anti-aliasing under 'border'