JavaScript developer hints - MacGapProject/MacGap1 GitHub Wiki
Switching on Developer Tools
You can switch them on by running the following on the command line. After this you should be able to right-click the window, as in Safari.
defaults write com.MacGap developer 1
Reloading the HTML page displayed in the MacGap window
In MacGap this can simply be achieved by:
window.location.reload()