I have added some boolean type checking and casting in save() and _validateSelect() function (in FormDisplay.class.php).
When saving: Settings - Main Frame - Browse Mode
- Iconic navigation bar = Yes
- Iconic table operations = Yes
the Iconic configuration value is stored as integer 0, 1, or string 'both'. Not false, true, or 'both'.
The rest of the code, use strict comparison (=== and !=== to boolean true or false), so sometimes the comparison failed.
save(): convert string '0' and '1' to false and true (for NavigationBarIconic and PropertiesIconic).
_validateSelect(): make sure that boolean value not converted to integer.