Observations: achecker.ca lists it as "potential problem" (instead of "known" or "likely"). They document this
script check in http://achecker.ca/checker/suggestion.php?id=86. They seem to justify the problem with guideline 1.4.1 Use of Color from WCAG 2.0.
You could only have a color-related accessibility problem with a
script element if you display this
script element, for example with the CSS
Assuming that you display the
script element, you could only fail the WCAG 2.0 guideline 1.4.1 Use of Color if the
script element’s color is used for a certain meaning¹ (instead of being pure decoration).
Assuming that you use the
script element’s color for a certain meaning¹, you could only fail that guideline if you don’t provide an alternative² to the color (e.g., text).
A tool can’t possibly check for 2. (if the color has a meaning¹) and 3. (if you provide an alternative²), so it would have to be always a potential problem, and for all (visible) HTML elements (
script is nothing special here).
tl;dr: Ignore it unless you display the
¹ A meaning could be, for example, when refering to the
script element’s content via its color: "See the JSON in red", "The blue text is authored by Alice", "Additions are green" and so on.
² An alternative could be, for example, when refering to the
script element’s content via its color and a textual character, an underline, etc. in addition: "See the JSON in red (marked with a
*)", "The bold blue text is authored by Alice", "Additions are underlined and green" and so on.