Refresh our patches to apply on top of thunderbird 1:68.5.0-1~deb10u1

Originally created by @intrigeri on #17481 (Redmine)

All branches FTBFS since 1:68.5.0-1~deb10u1 was uploaded to buster-security.

Feature Branch: bugfix/17481-refresh-thunderbird-patches

Edited May 15, 2020 by intrigeri

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