Ok, so the
legend.width is the available width for legend content - basically the columns and rows.
There is another property that needs to be adjusted if you want all the text of any legend entry to fit in a single line:
Increase the value of
legend.maxLineSymbols: 15 (default).
Please note that if you resize the chart, the entries are automatically divided into columns and rows.
In case you still want to have single column, then
legend.width value should be set fixed and smaller.
And be aware that setting
legend.maxLineSymbols value too large may hide label entries too soon (when resizing/decreasing chart container).