This issue is creating an associated MDL for an orphan TODO in tag/locallib.php, which I came across while working on [MDL-30992]...

"$max_tags_displayed = 10; // todo: turn this into a system setting"

In the function tag_print_description_box() we are currently setting $max_tags_displayed to 10. There is a todo attached which suggests turning this in code literal into a system setting.