I used netinstall-cli with -s userscript to send a configuration to a rb4011 along with the firmware. I did not expect that it would save that script in /system/default-configuration/custom-script, and will always use it when the reset button is used, which is actually a nice feature. However, it seems that it also uses it when /system/reset-configuration is used and I don’t see a way to get back to defconf. I even tried netinstall-cli with no -s and it still used the saved config as default config.
How can I remove the saved custom-script?
Hmm, I’m not sure the Linux version has the exact same “Apply default configuration” option like the GUI… That’s how you revert this typically.
Did you try a “-r” without the “-s”? The help is a little confusing what should happen, but sounds like it should remove your configuration.
-r
When the reinstallation process is performed, the configuration is reset, and for devices that have it, the default configuration may be applied, which is optional.
-r was the answer, thanks. It would be nice if it could be done without netinstall, though.
Fair enough. But you started with netinstall 
.
/system/reset-configuration no-defaults=yes keep-users=yes run-after-reset=customscript.rsc
does NOT cause it to be saved…