I have upgraded from 2.2+ to 2.3.2 and have created a problem where the navigation menu does not open and gives this error about being unable to get the value of the property 'init_add_tree' and refers to which ever page I am trying to open:
Message: Unable to get value of the property 'init_add_tree': object is null or undefined
I have had a similar problem before after an upgrade to 2.2, but that was a result of incorrect permissions, this time I have made sure the permissions are the same as the old version.
I have tried all the suggested remedies like purging the php cache and the ie cache, making sure all updates have been done on the server and I have run out of ideas. I can see this seems to be an ongoing problem for some but can't find a solution that works for me.
I would appreciate any suggestions that might solve this problem.