Recover the ability to add fields to a publish layout in ExpressionEngine
We recently had a problem where a custom field dragged onto a publish tab from the toolbar failed to attach to the tab. After some research it appeared others were experiencing the same issue with little success finding a solution. EE mods suggested upgrading, in some cases this solved the problem.
In the process of trying to fix I read a forum post suggesting the problem is caused when saving a publish layout. That led me to believe deleting the publish layout should fix the issue which it did. Upgrading may stop the issue altogether, I don’t know since I haven’t done so yet. If you want to fix it immediately then try deleting the publish layout first.
Open the toolbar on the publish page. Select the Member Groups from the list at the bottom of the toolbar. Click the remove button and see if that fixes your issue.
If it doesn’t or you have a different solution respond in the comments.