Column widths may be ignored due to two reasons:
1) incorrect configuration, e.g. the sum of all column widths is smaller than the width of the Grid. In such cases it is good to leave one column without a width, so that it expands as much as needed;
2) the column content is too large to fit in the specified width;
Enabling Grid scrolling applies a table-layout:fixed style to the table elements, which enforces the column widths even in case (2) above. However, you can't make the columns expand automatically in this scenario - this is possible only in auto table layout.
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