Describe the bug
When hovering of a horizontal bar chart, the tooltip pops up randomly on different places.

To Reproduce
Steps to reproduce the behavior:

1. Go to stats page
2. Hover over contacts bar chart
3. See tooltip over different bars

Expected behavior
The tooltip should be exactly on the bar, the mouse is over. No matter if the bar chart is horizontal or vertical.

Screenshots

System (please complete the following information):

• OS: Windows 10
• Thunderbird Version: 78.11.0 (32-Bit)

Additional context
None.