When you're building a regex, it pays to be very specific about the data you're expecting. So if your example says:

• The interesting data are of the form key=value; everything else can be ignored
• key is a string of \ws
• value is either a string of \ws or a quoted string that can contain any character but a double-quote

then you can build a regex to match a key:val pair pretty easily:

# NOTE: untested
/(\w+)=  # key
 (?:     # match either value:
    "([^"]+)"   |  # quoted string or...
    (\w+))         # non-quoted value
/xg
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