Hi 7thcircle!
Is that line before, or after:
/* That's all, stop editing! Happy blogging. */
It needs to be before that line. Have you tried disabling all plugins?
It is before that line, and it used to work. I have it in the same spot on other sites without any issues.
Also, no difference with all plugins disabled and twenty twelve theme.
UPDATE: looks like its the fault of the Groups Plugin. See comments on this answer: http://stackoverflow.com/a/27082044/661179
Actually… I’m having the same issue with twenty twelve installed.
Other sites that I manage that have the following defined appropriately don’t allow the plugin or theme editor links, update notifications, or install plugin/themes links/actions to appear.
define( ‘DISALLOW_FILE_EDIT’, TRUE );
define( ‘DISALLOW_FILE_MODS’, TRUE );
Core Version: 4.6.1
Update: Created an issue with itthinx on their github repo for Groups: https://github.com/itthinx/groups/issues/58