Thunderbird build failure

[Corpo]

Hi.

For the past couple of weeks I've been unable to update Thunderbird.

Last working build was 68.12.0_2.

Last try was with 78.4.0.

I get an expected build failure with the following:

gmake[5]: ***
[/usr/ports/mail/thunderbird/work/thunderbird-78.4.0/config/makefiles/rust.mk:299:
force-cargo-library-build] Error 101

gmake[4]: ***
[/usr/ports/mail/thunderbird/work/thunderbird-78.4.0/config/recurse.mk:74:
toolkit/library/rust/target] Error 2

gmake[4]: *** Waiting for unfinished jobs....

gmake[3]: ***
[/usr/ports/mail/thunderbird/work/thunderbird-78.4.0/config/recurse.mk:34:
compile] Error 2

gmake[2]: ***
[/usr/ports/mail/thunderbird/work/thunderbird-78.4.0/config/rules.mk:390:
all] Error 2

I'm on FreeBSD 12.1-RELEASE-p10, GENERIC, amd64. I update my ports tree
and my source tree daily with svn, (re)building as warranted. All is
well with all other ports. Firefox 82.0.2 built without a glitch.

Any suggestion on how I might debug this, correct the issue causing this
or further info needed?

Thx.