Tails Upgrader sometimes make device unbootable

It looks like the script that triggers the automatic upgrade is failing to see when there is not enough space available on the Tails partition.

Description of the error:
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Instead of receiving the message ‘Not enough memory available’, the script tries to write the new download, and it ends up with a corrupted boot folder.

What should happen instead:
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User should be advised to Update manually instead:

https://tails.boum.org/doc/first_steps/upgrade/#manual

Related issues

• Related to #10235 (closed)
• Related to #10347 (closed)
• Has duplicate #10292 (closed)

Original created by @emmapeel on 10239 (Redmine)