We have upgraded to Version 7.14.6 and since then the ListView of the Opportunities module stopped working. Loading the opportunities page would give an error with a message “If this error persists, please have your administrator disable Ajax for this module”. If you disable Ajax for that module then all you get is a grey page, no list of items.
At the same time the filter popup would show up without any fields.
After a lot of investigating I found out that what would break the Filter (and consequently the whole page) were the CreatedBy and ModifiedBy fields. Adding them would cause the issue, removing them would get the page loading again (and the filters working). That for every module.
Can anyone suggest a solution?