Build Number:6157 & 6819 (and probably all between and <6157)
1) Highlight some history text in the communication floater (IM/Local/Group)
2) Click the mouse pointer elsewhere (anywhere but the history)
3) Observe the highlighted text is still highlighted
This never happens in any other programme, at least on Win7.
This creates an issue when using the standard Dark Skin, as the history text is grey, and when you click the text input field it makes the highlighted selection also grey, making the text unreadable.
Enclosed are 2 pictures. Selection before clicking elsewhere and selection after clicking elsewhere.
NB: If you click again in the history window, the selected text does unhighlight.