Category Color not changing (bug)

When changing the category color on the back-end, the change (after saving) isn’t sticking. It reverts back to it’s original color. I have to clear the server cache, then I can make the change, but only once. I have to clear the server cache again, every time I want to make a change to a color. Our clients don’t have the ability to clear the server cache. Can you look into this bug?

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