I don't see why not. It can have the image stored in the ROM somewhere and factory reset may involve a low-level dump to the flash. In fact that would be the simplest way since the flasher then would not need to know anything about partition tables and file systems. It could be literally just a few dozen bytes long and completely stand-alone.

I am not saying this is how it is implemented in the N9 because I do not know. But exactly because I do not know, I would be wary of assumptions like the above until someone could confirm it with certainty, without "I'd imagine"

There is no known partition on N9 which can/could/does hold the firmware image. So it is not a 'I'd imagine' but more a 'pretty sure'

afaik even the Jolla does not do so but rely on btrfs functionality (wasting directly 1-2GB of full 16G), right? At least for partition28. For the others it might be.

That's why I was careful to use different words for ROM and flash
But yeah, I agree what I said is possible but unlikely.

OK, I did clear the device. and everything is fine, ubiboot still works and harmattan aslo boots up. All partitions are also OK. No problem (yet).

I guess clearing the device just clears the home partition and leave rootfs untouched (removes all the installed apps though)

Because i had added the repomirror list manually, it is still there. i am able to enable developer mode(there is an exclamation mark beside the switch, don't remember if it was always there), also the ubiboot config files were in there. they are also fine.

How does this removal of apps happen? where is the information about the user installed packages stored (i don't know how apt works)?
And is it possible to edit it manually to have some important apps preinstalled? like terminal filecase etc. What information should i add there?
Also what all packages does terminal require? I want to have developer mode enabled by default.

EDIT: Nothing was cleared, i still have my old accounts, old app settings, contacts, call logs, photos, everything. also root's command history is available. all it did was uninstall apps. I guess it tried to look for old partitions didn't find them so didn't do anything. But how does it look for these partitions? if it is by partition number then root should have been gone.
Can we get the script or anything which is responsible for resetting and clearing the device? or is it integrated into settings?

Ok so i have that problem now, where installing apps force closes all other apps. So do i have conflicting keys? I know the fix by replacing libapplauncherd.so. but will this cause any problems in future?

I found this. But the size of all the packages here together is 1.7MB. But while installing developer mode from device it downloads 2.2 MB of dependencies. So are any packages missing?

Which would cause problems? Patching libapplauncherd or having conflict in aegis keys?
The former will not cause any problems, the latter might but usually doesn't.

I read from here that the problem is caused when in open mode and if there are conflicting aegis keys.
So how do i know if there are conflicting keys? I did a clean flash and have not booted with anything except openmode kernel. Still i had that problem with force closing of apps.

The only way (well the only easy way without special tools) to accomplish a clean openmode installation with matching aegis keys is to flash the device back-to-back closedmode/openmode. (see http://wiki.maemo.orgUbiboot#Flash_t...clean_state.29 for explanation)

This is a way to make sure that after fresh flashing the device will boot up in open mode the first time it boots, which is when the aegis keys are created.

I don't remember now though, but i have done a back to back flash i guess, don't want to flash again.
What kind of problems can i expect if i have closed mode keys?