mirror: ${name}: file size decreased during transfer

This is on travis-ci, with dist=trusty

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Get:1 http://us-central1.gce.archive.ubuntu.com/ubuntu trusty/main amd64 lftp amd64 4.4.13-1 [422 kB]
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Then, when i do
$ lftp -c mirror --delete --loop --verbose=1 https://something/ ./

It fails:
Transferring file `name'
mirror: name: file size decreased during transfer

This does not happen with lftp 4.8.0 in debian sid.
I'd guess it might be https://github.com/lavv17/lftp/issues/54, but it should already be fixed in 4.4.13