%ruleContext% + %ruleKey% > %ruleOutput% save(%optName%)
The save command is used on the right hand (output) side of a rule to save a current option value in the Windows registry. This option value will then become the default option value for future use. It will typically be used after a set command to make the dynamically changed option value change permanent.
+[CTRL ALT "1"] > set(opt1='1') save(opt1)
The key sequence matched by the rule will change the option value to '1' and make that change permanent.
The save keyword was introduced in Keyman 8.0.