Hello Florian,

> Thank you for the quick patch!  Clearly you have been spot-on.
> “Partition formatting is in progress, please wait” is displayed
> considerably longer but eventually succeeds.  I tried 3 times
> successfully with your patch.  I tried again without your patch and it
> failed.  I tried once more with your patch and formatting succeeded
> again.

That's good news! Here's a more complete patch that I intend to push on
the 1.2.0 branch. It logs the time spent waiting for disk
synchronization.

It would be great if you could test it one more time, so that we know if
4 seconds is enough or if we should use an even higher delay.

Thanks again,

Mathieu