I've heard that you must make at least n (6?) character changes in order to suggest edit, yet here's an edit with 0 changes. You can view sources from edit history: before and after.
Were rules changed recently?
The rules did not change, there were 6 spaces added at the end.
If we notice a pattern of abuse we will add more cat-and-mouse "stop adding almost nothing checks". It is painful, cause you add them and then someone adds
<!-- ha ha cheated --> or blank unicode chars and so on and so forth.
Note the system, by design, protects itself from this kind of abuse. If people suggest these kind of crap edits, reject them and then the people doing so will be banned from edits.