Slider setReadOnly sets contrast incorrectly

URL of gitlab repo: https://gitlab.pavlovia.org/djangraw/losasurveytask/
URL of experiment: https://pavlovia.org/run/djangraw/losasurveytask/html/

Description of the problem: I have a task where empty questions on a survey are “grayed out” by setting the read-only property of the slider to true. This cuts the contrast in half. But if, on the next iteration of the loop, I setReadOnly back to true, the contrast is not restored to its original value. And if I setReadOnly to true a second time, the contrast is halved a second time.

For example, in the picture below, the second-to-last line should be full contrast (not half), and the last line should be half-contrast (not quarter).

I think the problem is in Slider.js here where there should be an else statement that doubles the contrast. Does anyone know a workaround I could use in the meantime?

Thanks for this. I’ve put a pull request with the fix at

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