So this does not appear to be a bug, but just the outcome of using either the Bilinear or Trilinear filter for this specific texture sheet. I do not see this ‘color bleed’ using the Default (from Texture Group) settings or using the Nearest Filter. Especially if these artifacts do not appear in other textures using the same filters.
Unless there is a specific reason you have for using Bilinear or Trilinear filtering for this specific texture sheet, I suggest staying with the Default filter as it produces the correct results.
Thanks,