Problem in some elements

I’m having trouble adding some elements. For example when I add Heading and Icon elements are a long time “loading” but does not show the options. Then I click OK and added the element with default options and even gave try I can not edit them.

I’m using Chrome but I’ve tried using Firefox and have not had success.

I did not try with other elements yet, these were the only two who tried yet. The text input element works normally.

Thank you!