From Enigmail changelog:
Released 2017-12-19, works with Thunderbird 52.0 - 55.0b1 and SeaMonkey 2.46 - 2.52.
This release addresses security vulnerabilities discovered by Cure53.
See $URL for details.
@ Maintainer(s): Can we already start stabilization of =x11-plugins/enigmail-1.9.9?
(In reply to Thomas Deutschmann from comment #1)
> @ Maintainer(s): Can we already start stabilization of
add them up and get to marking.
please test and mark stable: =x11-plugins/enigmail-1.9.9
Stabilization complete. Tree is clean.
GLSA Vote: No