Another case where TMW is too clever by far in creating an opaque graphics object -- you have to use the hidden properties to find the underlying pieces.
hAx=h.NodeChildren(3); % return the heatmap underlying axes handle
hAx.FontWeight='bold';
hCB=h.NodeChildren(2); % the wanted colorbar handle
hCB.FontWeight='bold';
You can further explore the handles in the NodeChildren array at your leisure.
And, add your voice to the complaints to TMW about their being hidden properties and this propensity to do such nasty things to their users causing them to waste precious billable hours on trivia. If I were still consulting actively, I'd raise holy cain with them. As is, I complain here every chance I get for what good it may do and have communicated my distaste for the policy directly.
