The SSRS team seemed to be trying to implement intelligibility, but did not complete it. I assume they really display:
<div style="word-wrap:break-word;white-space:pre-wrap;" class="A28f9f53b98ae45d6a21919d29df775da131">Text </div>
but they skip the word-break property in their markup. (or css is broken because it requires both word-wrap:break-word not work? :) here is a nice investigation on this)
In any case, to break the text in the columns, add the following css to your page using the report viewer:
div [style*="break-word"] { -ms-word-break: break-all; word-break: break-all; word-break: break-word; }
NB: this will NOT interrupt text in column headings (I prefer to set column heading lines manually, as the text is fixed and known at design time).
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