More readable styling for chart tooltips

[sc1f]

Feature Request

Description of Problem:

When looking at tooltips on charts, the decimal point between floats are unclear and hard to read at a glance:

Potential Solutions:

Tooltips should be styled with a clear differentiation/highlight on the number, or the bold styling should be removed as it seems to (at least for me) hinder quick at-a-glance readability.

[NickSneo]

I am new to the open-source world, so can I take this issue. Also, I just need to add monospace font for the hypergrid, right?