Hello @Fabby, thanks for your effort. I have a “cold backup” of my main working drive only, so in this case I’ll do a backup of data from the HDD and then re-format it (avoiding extended partitions :)). It’ll be the easiest thing in the end (though I’ll be still wondering why grub
cannot be reinstalled to a working state there…).
Happy Manjaro days to you.
PS: You wrote you deleted the solution, but the question is still shown as “solved”. I don’t expect there would be fresh clever ideas from other readers, but perhaps, if the question would be marked unanswered… you never know. Thanks.
PPS: In the deleted post, there was a link where to report the Calamares bug. Could you please re-post it, so that I don’t have to google it…? Thanks again.