Thanks for all the help, I really appriciate this!
I could not get rid of the (in my opinion ugly) green color which marks highways (with no traffic) with the Google styling as mentioned in the reply of bradyemerson.
I’ve found another solution within the MM Forum so I’ve copy/pasted it. Don’t know if this code is properly correct but it works for me and maybe others can benefit from it.
In the module MMM-iFrameReload i’ve changed te line:
iframe.style = “border:0”
iframe.style = “border:0;-webkit-filter: grayscale(100%);filter: grayscale(100%);”