Description
See here: http://jsfiddle.net/cpanmc8m/
When hovering over the chart, the x-value identified by the hover text differs between the two traces, even though the traces have the same x-values. For example, the scatter trace may show that the hovered x-value is 40, while the bar trace shows hover text for value 39.
Increasing the amount of data relative to the chart width appears to exacerbate how far apart (numerically) these hover text values are. On the other hand, reducing the amount of data seems to make the hover text work as expected.
The immediate culprit seems to be the space character in each x-value. Replacing the space character with a letter or with a tab character does not cause the same issue. Instead, this causes a reversion to the behavior described in #780 (bar trace hover text is not shown).