Whenever I install a new widget, I don't know if it supports ICS or not immediately because it won't show up on the Widgets tab until I restart the phone. It is highly inconvenient. Is there a way to force Trebuchet (my home app) to reload the widget list everytime I install a new app?
In my experience, Trebuchet does always reload the list. I just have to wait a couple of seconds.
If it really doesn't, you can go to the Applications section in the settings menu, select Trebuchet and Force Stop it. That should force it to drop any state, including the widget list.