People putting an excessive amount of asterisks, at signs and underscores in their profile summaries are causing issues with some of the search pages. People end up getting a scroll bar at the bottom of their screen where they have to scroll to the right to see the whole page.
So, now you cannot enter more than three of the same characters in succession:-
Allowed: *** or @@@ or ___
Not allowed: **** or @@@@ or _____
Also, as (almost) no word is longer than 30 characters, you cannot enter any more than 30 characters without breaking it up with a space.
These measures will ensure that if your profile is appearing, it will be visible on the screen without the viewer needing to scroll.