I want to mention: There are still some problems with it.
In Firefox, rigth clicking always opens an context menu (but also gives an arrow/circle). But it's always red or green, never blue or golden.
In Opera I get all colors, the circles work perfectly. But arrows are a problem: Green arrows only work with shift+left click, not with right click. Red arrows never work, but blue and golden do.
€: Now I found out, that golden arrows don't always work in Opera. Also you can make blue arrows by holden Alt + right click. You don't need shift then... so confusing. This feature is so unreliable, that (imho) nobody can use it