Hello @Thomas Dreibholz,
It's been 332 days since this issue went into Incomplete and we haven't heard
from you on this.

At this point, our policy is to Close this issue, to keep things from getting
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Hello @Thomas Dreibholz,
It's jira-bot again. Your bug report is important to us, but we haven't heard
from you since the previous notification. If we don't hear from you on
this in 7 days, the issue will be automatically closed.

Hello @Thomas Dreibholz,
I'm jira-bot, Percona's automated helper script. Your bug report is important
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I encountered the same problem in 2.4.6

xtrabackup version 2.4.16 based on MySQL server 5.7.26 Linux (x86_64) (revision id: c807cfa)

Hi @Thomas Dreibholz

Thank you for the update.

There are lot of bug crash bugs fixed between the version you are using and the current latest version.
please upgrade xtrabackup to the latest version 2.4.14, also if possible upgrade percona server to the latest version 5.6.43.