May you try following and share your feedback accordingly:
1. May you try clearing your browser cache or try incognito mode.
2. Make sure your browser is updated.
3. Try it on some other browser i.e. either Safari Firefox.
First time that I tried color.adobe.com was today, and I cannot save any color theme. I see a message of 'Script…Void(0)' when I hover the mouse over the SAVE button. I've the same problem whether I use Safari, Chrome, or Firefox on my iMax using El Capitan. All web browsers have been updated as of Nov. 2, 2017, and I've cleared cache and history, which of course forces me to log in with my Adobe ID. I've tried the icognito mode using Chrome, and I have the same problem where I can't save the color theme.
I must add that when I activated the Adobe Color Theme extension within Photoshop on my iMac, the last color theme that I created via the website was there in the extension window.