Use monospace font for timestamps
I find it very confusing that message timstamps are not aligned in the chat window. Frankly speaking, it looks awful:
Attached in the message is a simple patch that assignes monospace font to the timestamps which makes the chat window look like this:
Of course, it needs some work to meet you coding standards (e.g. the font should be customizable and so on). 0001-Monospace-font-for-timestamps.patch