Further fixes to make things work in Chrome again

fixes all the stuff that was broken in chrome stable, still works in FF. Please test:

* [ ] basic loading of the designer page
* [ ] adding a component shows the comp, the two arrow buttons to the left and right of it, and the listen/broadcast channels
* [ ] clicking the listener/broadcast arrow button pops up a selector menu
* [ ] picking a new color for a listener/broadcast changes the channel visualisation