[SOLVED] Update 3.6.4 -> 3.7.7

I finally upgraded to 3.7.7, now one problem turns up:

I am using three footer widgets with separate styles for their headers and contet. Until now that worked just great. But after the update, the styles don't work anymore. I am pretty sure that's because Atahualpa seems to add backslahes and quotes to the styles like this

The forum swallowed the first backslash which is right in front of the quote.

I am using this code in the footer:
I have no idea why Atahualpa (3.7.7) adds these backslashes. 3.6.4 did not do that. What could be wrong here?

I am using Wordpress 3.3.2