Override settings
If you need to start mythfrontend and temporarily override a setting in the database, simply use the -O command-line argument:
mythfrontend -O $somesetting=value
Note that command-line overrides are meant for short-term overrides. You should not normally need to use overrides. Instead, if you always need a specific value, set that value appropriately in mythtv-setup or mythfrontend settings.
For example, to start mythfrontend with the qt painter rather than OpenGL, use mythfrontend -O ThemePainter=qt
To start mythfrontend with the blue theme, use mythfrontend -O Theme=blue
Tip: The value of $somesetting can be anything from the settings table (within reason)
Also available (as described by mythfrontend --help) is a geometry setting to allow you to resize the mythtv GUI:
e.g. mythfrontend --geometry 1280x720
To start mythfrontend at 1920x1080 with the Minimalist-wide theme, use mythfrontend --geometry 1920x1080 -O Theme=Minimalist-wide