Tooltips on Mac use "Ctrl" instead of control (cloverleaf symbol)
Created originally on Bitbucket by etrue
Observed in version 4.4.1 (Mercurial-4.4.1, Python-2.7.11, PyQt-4.11.4, Qt-4.8.6) on MacOS 10.13.4, but I think this bug has existed since 3.x.