Matt C. reported running a Jython script in BOY which triggers on a slow changing PV. Setting a value for a combo box does not work on the first time through the script (when the OPI is started), but does work when the PV triggers.
Doing something similar with a text box works fine on the first time through.

The script looks like this, and is attached to the display:

from org.csstudio.opibuilder.scriptUtil import PVUtil

display.getWidget("Combo").setPropertyValue("items", ["A", "B", "C"])
display.getWidget("Combo").setValue(1)
display.getWidget("Text").setPropertyValue("text", "hello")

When I attach similar code directly to a Text Update widget

widget.setPropertyValue("text", "hello")

the text is updated by the script, but when attaching this to a Combo,

widget.setPropertyValue("items", ["A", "B", "C"])

the Combo continues to show the items which were originally configured.

So overall:

• Updating the combo items from a widget script doesn't work at all
• Updating combo items from a display script succeeds after several runs
• Updating a text update widget text succeeds in all those cases