1. New Text Document.
2. In Styles and Formatting pane → Paragraph styles, right click and select New.
3. In the Style Name type “test” and Inherit from to None and OK.
4. Right click test style and select New.
5. In the Style Name type “CM1” and OK.
6. Right click test style and select New.
7. In the Style Name type “DMM1” and OK.
8. Right click test style and select New.
9. In the Style Name type “M” and OK.
8. Right click test style and select New.
9. In the Style Name type “W” and OK.
10.Right click test style and select New.
11. In the Style Name type “common” and OK.
Click on these styles to highlight them.
Result:
The name is not fully covered by the highlight.

For other names of varying lengths, the highlight is either the same length as the name or longer.  It looks like at times the length is determined by a count of characters and multiplying that by a pixel width which does not take into account the width of 'm' or 'w'.  But that cannot be what is happening because if you create a style named “memory”, which has two 'm's and is the same number of characters as “common”, then it is fully highlighted.  “common” is wider than “memory” though.

An example of the highlight longer than the name is “lily”.  Compare that to “book”.  The highlight is the same length.  The 'i' and 'l' make the word shorter.

The Character Styles does not have this problem.

Version: 4.4.3.2
Build ID: 88805f81e9fe61362df02b9941de8e38a9b5fd16