Similar to this suggestion to change the background color of a highlighted text/text with an inline comment, this is a suggestion to change the default color or have it using a color that provides a higher level of contrast so it can be distinct in the page.

While allowing the 'inline comment' highlight color to be changed would also (as the suggestion above) would help, users would still need to perform this modification.

Why this feature?

Users that have vision limitations might not be able to see it properly. Even that some users have options like inverted colours for their System, due to the low contrast for the highlighted text, this would still have difficulties to be displayed (instead of yellow x white, which is the default color, it is darker blue x black).