Looking into this a bit further, this seems to be a matter of the KDE frontend not calling allow_change_step(False) while processing after a partition is edited in the UI (which is probably exacerbated by the recent slowness of the KDE frontend). Giving the partitioner sufficient time to complete each step does not result in an AssertionError.
I haven't managed to reproduce this using an English locale.
Looking into this a bit further, this seems to be a matter of the KDE frontend not calling allow_change_ step(False) while processing after a partition is edited in the UI (which is probably exacerbated by the recent slowness of the KDE frontend). Giving the partitioner sufficient time to complete each step does not result in an AssertionError.
I haven't managed to reproduce this using an English locale.