I've found a simple fix for EFM.
Thanks to hints in Matt's post here
(as I am NOT a PHP programmer) but it turns out the problem is the $this variable.
Here is the fix:
Go to your file
find the file
In that file change all occurences of
(or some other value that starts with a dollar sign and is not the same as $this)
There were 10 such occurences in my index.php file.
I changed them all, saved the index.php file, and now it works again.