Remove legacy handyClicksPrefSvc.enc()/dec() usage
Improve performance of "precompileCustomTypes" option:
add delays between new Function() calls
Add ability to cache already created custom functions
Preference: cacheCustomFunctions
Add special error message for syntax error in custom function
Add support for Browser Console (but prefer Console², if available)
Open Browser Console not only from browser window
(but at least one browser window should be opened anyway...)