The buttons "Previous/next document with errors" on the Web Verification station are inactive during the Verification of the server-based project.
The documents don't have warnings or errors.
It doesn't require any specific actions.
If documents in the task for the Verification don't have errors or warnings, the mentioned buttons will be inactive. Otherwise, documents would be marked by red or yellow flags as on the screenshot below:
The functionality of these buttons should not be taken as toggling between pages.