Unless you have content that shows up as a long repeated string of characters, this won’t happen on any of your pages. If you write normal content with paragraph, spacing, periods, etc then it will stay within the defined content width/area as it’s designed to. The same string of characters could happen to other themes/sites too unless you directly add a word-wrap.
If for some reason you do have repeatable characters like the page in your link then you can add this to your content – word-wrap: break-word;
.content {
float: right;
width: 700px;
word-wrap: break-word;
}
This won’t happen to your real/regular content so I wouldn’t worry about it.
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