Trying to overwrite ... which is different from other instances of package

Removing the change-log file helped me out here. (If you want you can do a backup, but it is only a change-log file.)

sudo rm /usr/share/doc/libcairo2/changelog.Debian.gz

And then trying again to update. I did it via;

sudo apt-get update

and then

sudo apt-get upgrade

You could try it again with the intel update tool.

I have a similar problem with libmysqlclient21.

The solution was found in Debian Bug Report. The next command helped me fix the issue:

sudo apt-get install -f -o Dpkg::Options::="--force-overwrite" libmysqlclient21

Then continue with the normal upgrading process.