Sometimes the Web Client or a URL integration is not working as expected. To investigate the behaviour it could be helpful to get the script errors. But there are set off by default, so it is necessary to activate them.
To activate it go to the Internet options > Advanced > Browsing.
Set the following options:
- Disable script debugging (Internet Explorer) = off
- Disable script debugging (Other) = off
- Display a notification about every script error = on