Windows 10, Version 6.8 - 'H' isn't working for me. I can't find it in Preferences->Shortcuts; but I didn't think it was customisable, so that doesn't surprise me.
And I lost my custom shortcut to Manage Categories (Shift+Ctrl+A), but was able to reinstate it. Interestingly, when I reinstalled 6.7.1 it came back again - then when I reinstalled 6.8 it was gone again
BR