Attachment tab from page gets badly rendered when clicked and attachment number >= 10

Steps to follow to reproduce:

-Login as any existing user
-Attach 10 or more unique files to a page (Note : there must be 10 or more different filenames)
-Go at the bottom of the page, where the attachments tab is located. You should see there, in the brackets, the number of current attachments on the page)
-Click on the Attachments tab to view them.

Result:

• As can be seen, when the attachment tab is clicked, the bracket with the number of attached files goes under the button.