Notifications tabs do not work

Notifications tabs do not work

Hello,

If we go to Admin -> Notification page, the tabs Request, Solution, Task, and Mobile Push Notification etc are visible but not clickable.
Chrome, IE give an error when we click on them. See attachment for the error. Discription: 

Failed to load resource: the server responded with a status of 404 (/custom/scripts/CustomScripts.js)
sd_setup.js?9109:13 Uncaught TypeError: Cannot set property 'className' of nullchangeNotificationTab @ sd_setup.js?9109:13(anonymous function) @ VM1334:1

We are currently at SDP 9.1 Build 9109.

Can anybody help? Regards,
Jeroen van Lieshout

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