Add new Event generates Notices

This is after update to beta 7a

With the Safari browser on Mac OS X, the horizontal tabs are visible just above the Notices. The default Main Menu items are displayed normally, but the new ones appear as narrow 'fingers' with no text. These are Book, Section, and Link pages with Menu Links. A pair of Notices seem to be generated for each on these Blank Tabs.

A difference in the number of Notices was also noted between a test site and the production site. This also was a result of the difference in the number of Tabs.

The odd Tabs are not visible in other browsers/OS (only Mac OS Lion) I have used. In those, the overlay covers the Tabs.

The update path was beta6 to beta7a. "backup_migrate" with "backup_migrate_files" were the only added modules.

All modules -indicating it in Features- were reverted after the Update.

I just added a Section with a Menu Link to my Staging instance. This increased the number of Messages in the Log from 6 to 8 after clicking "Add a new Event":

Notice: Trying to get property of non-object in node_page_title() (line 2075 of /home/example/public_html/Staging/modules/node/node.module).