Red sand block missing from suggestion list via /fill command

When you use the fill command, the block item for red sand is missing from the suggestion list. See photo attached. You will notice that the regular sand variant is in the list, but the red sand variant is missing.

Steps to reproduce

• Type out this command i.e. /fill ~10 ~ ~10 ~-10 ~ ~-10 sand
  or

• Type out this command i.e. /fill ~10 ~ ~10 ~-10 ~ ~-10 red

• Observe that red sand isn't also offered as a string suggestion.