Version: (using Devel) Installed from: Compiled sources On a bug screen there should be an n-dash separating bug number from its description in the page navigation bar. Apparently the entity is double quoted, which makes it render as '–' instead of '–'. A trivial fix would be to replace the entity with the unicode character. It could be useful to inquire as to why it happens, though, in case it's not an isolated mistake but a bug somewhere in the stack.
Reported at bug 199022 Thanks *** This bug has been marked as a duplicate of bug 199022 ***