The characters in the headers of GameList columns are normally non-bold, but they became bold when all the games in a database are loaded (or present in a selection) and again non-bold when no game is present.
When one clicks on one of the header when they are bold, all of them remain bold except the header clicked, which turns non-bold.
A search performed (for instance) in "White" makes all the header be bold if at least one game is found. The behavior is different for a search performed in "Nr", because the headers are non-bold if at least one game is found.
As a consequence, the headers in GameList often dance between the two states bold/non-bold, annoying the user. Having all of them always non-bold would be perfectly fine.
Fixed by commit 932.