Colour markers don't work

I had it several times by now that I added some chord info to a remix of someone's track, but when trying to put in colour markers for the different verse or chorus parts, that didn't work. Last time I tried I could have put in the second colour, but not the first. Somehow that behaves strange, haven't tried it with anything else than Firefox tho, next time I'll try Chrome (or Chromium).

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