If you want long words to be wrapped instead of overflowing the column (like shown below for column K), add word-wrap: break-word; to the table style. 

If you find that your widths are not being honored, it's possible that Confluence is setting the column widths to a static width. This can occur if you drag a column to set the width. Confluence tables have a setting to be either Responsive or Fixed width. We have seen cases where even if the table is set to Responsive, Confluence still applies the static widths.

To correct this behavior, edit your page and click on your table. You are then presented with a Table toolbar in the Confluence page editor. Click the Responsive dropdown, select Fixed width, then immediately click the dropdown and select Responsive. This seems to reset the table to a responsive setting and clears the fixed widths. Now save the page and view the table.

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