Opera: domain extracted from cookies4.dat missing '.' at start

[srlehn]

Checklist

• I have searched the issue tracker for open issues that relate to the same problem, before opening a new one.
• This issue only relates to a single bug. I will open new issues for any other problems.

Describe the bug

How to reproduce

kooky -e -d google.com -n NID

or choose other common cookie for comparison with other browser extractors

Example code

Kooky version

@iter_rangefunc, bf04c09

Go compiler version

1.22

Browser

Opera

Operating system and version

Linux