Does WebGL 2 support linear depth texture sampling?
The spec says depth textures are not filterable.


  3.8.13
  
  ...
  
  Using the preceding definitions, a texture is complete unless any of the following conditions hold true:
  
  
  The effective internal format specified for the texture arrays is a sized internal depth or depth and stencil format (see table 3.14), the value of TEXTURE_COMPARE_MODE is NONE, and either the magnification filter is not NEAREST or the minification filter is neither NEAREST nor NEAREST_-
  MIPMAP_NEAREST