In the source editor and in the viewer, the world that doesn't fit on the line, it results in a split word in the new line. For example:
I'm not usi
ng the mous
e at this m
You can get more information about line-break in markdown editors.
Maybe I badly explained. The "problem" is in the editor, that splits the words at the end of line, leaving some letters of that word, at the beginning of the new line! :)
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