Sorry I don't know English, this is from Google Translate.
I registered the account, but I can't use the add to group. When I click Add to group, a page pops up asking me to create a new group name. After I finish typing, I click Create, but nothing happens. Restart the browser is still the case, I am in China. , using a VPN.

Why didn't anyone answer me? I also sent an email to the administrator, but I didn't receive a reply. This matter is very important to me.

Click on the link "My selections" at the top of your screen.
The group / selection you created should be here.

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The selections are used to gather fonts, in order to compare them side by side even if they are not followed in the themes or the alphabetical sort.

You don't have any selections groups.
Browse the site and click on "Add to a group" above a font.）
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Thank you, this is what it shows, I still can't solve my problem.

Click "Add to a group" and then you will be able to create a new group.

I know it should be done, but I can't create a new group and clicking it doesn't respond.