Re-import secure-account-creation patch series for thunderbird

Originally created by @anonym on #16147 (Redmine)

In our thunderbird repo we should import these patches into tails/stretch, replacing debian/patches/secure-account-creation/:

git checkout secure_account_creation-60.3.0
git format-patch upstream/60.3.0..

Edited May 15, 2020 by anonym

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