Thanks for the hint. I installed that optimizer but even that cannot cache the cb files. Here is the network traffic. As you can see the version changes with every request and hence cannot be cached:
Code:
cb12.min.js?v=77b289b226f3a8af&_=1491342666177 GET 200 xhr jquery-2.1.3.js:8625 3.3 KB 842 ms
jquery.qtip.min.js?v=77b289b226f3a8af&_=1491342666179 GET 200 xhr jquery-2.1.3.js:8625 16.1 KB 1.11 s
jquery.cbtooltip.min.js?v=77b289b226f3a8af&_=1491342666180 GET 200 xhr jquery-2.1.3.js:8625 3.6 KB 857 ms
cbcondition.min.js?v=d6acc615f28600ba&_=1491342666181 GET 200 xhr jquery-2.1.3.js:8625 2.6 KB 867 ms
jquery.validate.min.js?v=77b289b226f3a8af&_=1491342666182 GET 200 xhr jquery-2.1.3.js:8625 7.6 KB 888 ms
jquery.scrollto.min.js?v=77b289b226f3a8af&_=1491342666183 GET 200 xhr jquery-2.1.3.js:8625 1.5 KB 828 ms
jquery.cbvalidate.min.js?v=77b289b226f3a8af&_=1491342666184 GET 200 xhr jquery-2.1.3.js:8625 6.4 KB 924 ms
cb12.min.js?v=77b289b226f3a8af&_=1491342666186 GET 200 xhr jquery-2.1.3.js:8625 3.3 KB 850 ms
jquery.qtip.min.js?v=77b289b226f3a8af&_=1491342666188 GET 200 xhr jquery-2.1.3.js:8625 16.1 KB 1.14 s
jquery.cbtooltip.min.js?v=77b289b226f3a8af&_=1491342666189 GET 200 xhr jquery-2.1.3.js:8625 3.6 KB 880 ms
cbcondition.min.js?v=d6acc615f28600ba&_=1491342666190 GET 200 xhr jquery-2.1.3.js:8625 2.6 KB 602 ms
jquery.validate.min.js?v=77b289b226f3a8af&_=1491342666191 GET 200 xhr jquery-2.1.3.js:8625 7.6 KB 868 ms
jquery.scrollto.min.js?v=77b289b226f3a8af&_=1491342666192 GET 200 xhr jquery-2.1.3.js:8625 1.5 KB 898 ms
jquery.cbvalidate.min.js?v=77b289b226f3a8af&_=1491342666193 GET 200 xhr jquery-2.1.3.js:8625 6.4 KB 916 ms
cb12.min.js?v=77b289b226f3a8af&_=1491342666195 GET 200 xhr jquery-2.1.3.js:8625 3.3 KB 862 ms
jquery.qtip.min.js?v=77b289b226f3a8af&_=1491342666197 GET 200 xhr jquery-2.1.3.js:8625 16.1 KB 1.13 s
jquery.cbtooltip.min.js?v=77b289b226f3a8af&_=1491342666198 GET 200 xhr jquery-2.1.3.js:8625 3.6 KB 851 ms
cbcondition.min.js?v=d6acc615f28600ba&_=1491342666199 GET 200 xhr jquery-2.1.3.js:8625 2.6 KB 788 ms
jquery.validate.min.js?v=77b289b226f3a8af&_=1491342666200 GET 200 xhr jquery-2.1.3.js:8625 7.6 KB 913 ms
jquery.scrollto.min.js?v=77b289b226f3a8af&_=1491342666201 GET 200 xhr jquery-2.1.3.js:8625 1.5 KB 914 ms
jquery.cbvalidate.min.js?v=77b289b226f3a8af&_=1491342666202 GET 200 xhr jquery-2.1.3.js:8625