Today after a BIOS upgrade, I almost thought I had locked myself out of my computer. Neither Windows nor Kubuntu would boot, and I was running out of ideas.
After many dead ends, and a couple of frustrating and scary hours, an eventual good web search told me that the upgrade had probably reset my BIOS setup, including the SATA mode.
After setting it back to AHCI, everything went back to normal.
[Notice Regarding the Transfer of the mstdn.jp / mastodon.cloud Services] We have received several inquiries showing interest in a transfer following the announcement of the end of the mstdn.jp and mastodon.cloud services. As a result of subsequently evaluating the situation and making preparations, we have decided that the corresponding services will be transferred to Sujitech, LLC. on June 30. Thank you.