Upgrading from PhpMyAdmin 18.104.22.168 (and earlier versions) to 4.6.0 breaks table export (and when many upgrades from earlier versions) also the "Server: Localhost" breadcrumb access.
I have raised a bug report with PhpMyAdmin folks here: https://github.com/phpmyadmin/phpmyadmin/issues/12159
, and they fixed that for 4.6.1, but also referred to fact that PhpMyAdmin should never be upgraded by file-overwrites, but always by first deleting previous files then writing new ones: https://github.com/phpmyadmin/phpmyadmin/issues/12159#issuecomment-20636...
Never extract the new version over an existing installation of phpMyAdmin; we had evidence of problems caused by this.
Please consider changing the upgrade method of PhpMyAdmin, as it obviously leaves old files that are potentially vulnerable.