new file mode 100644
--- /dev/null
+++ b/build/mozconfig.no-compile
@@ -0,0 +1,19 @@
+ac_add_options --disable-compile-environment
+
+# In case mozconfig.cache was already included
+unset CCACHE
+unset SCCACHE_VERBOSE_STATS
+# In case it wasn't
+NO_CACHE=1
+
+# Override any toolchain defines we've inherited from other mozconfigs.
+unset CC
+unset CXX
+unset HOST_CC
+unset HOST_CXX
+unset RUSTC
+unset CARGO
+unset MAKECAB
+unset TOOLCHAIN_PREFIX
+unset BINDGEN_CFLAGS
+unset LLVM_CONFIG

--- a/mail/config/mozconfigs/linux32/l10n-mozconfig
+++ b/mail/config/mozconfigs/linux32/l10n-mozconfig
@@ -3,18 +3,17 @@
 
 # Disable webrender on Linux buildbot builders to avoid the Rust requirement
 # of libX11 version > 1.4.99.1 (see bug 1350011).
 ac_add_options --disable-webrender
 
 ac_add_options --enable-application=mail
 ac_add_options --enable-update-channel=${MOZ_UPDATE_CHANNEL}
 ac_add_options --with-l10n-base=../../l10n
-# The compile environment is needed for Linux, see bug 1349300 and bug 1311045.
-# ac_add_options --disable-compile-environment
+. $topsrcdir/build/mozconfig.no-compile
 
 # Build lightning locales
 ac_add_options --enable-calendar
 
 # Needed to enable breakpad in application.ini
 export MOZILLA_OFFICIAL=1
 
 # For NSS symbols

--- a/mail/config/mozconfigs/linux64/l10n-mozconfig
+++ b/mail/config/mozconfigs/linux64/l10n-mozconfig
@@ -3,18 +3,17 @@
 
 # Disable webrender on Linux buildbot builders to avoid the Rust requirement
 # of libX11 version > 1.4.99.1 (see bug 1350011).
 ac_add_options --disable-webrender
 
 ac_add_options --enable-application=mail
 ac_add_options --enable-update-channel=${MOZ_UPDATE_CHANNEL}
 ac_add_options --with-l10n-base=../../l10n
-# The compile environment is needed for Linux, see bug 1349300 and bug 1311045.
-# ac_add_options --disable-compile-environment
+. $topsrcdir/build/mozconfig.no-compile
 
 # Build lightning locales
 ac_add_options --enable-calendar
 
 # Needed to enable breakpad in application.ini
 export MOZILLA_OFFICIAL=1
 
 # For NSS symbols

--- a/mail/config/mozconfigs/macosx64/l10n-mozconfig
+++ b/mail/config/mozconfigs/macosx64/l10n-mozconfig
@@ -1,15 +1,14 @@
 ac_add_options --enable-application=mail
 ac_add_options --enable-update-channel=${MOZ_UPDATE_CHANNEL}
 ac_add_options --disable-install-strip
 ac_add_options --enable-profiling
 ac_add_options --with-l10n-base=../../l10n
-# Disabling is needed, see bug 1345422 comment #58.
-ac_add_options --disable-compile-environment
+. $topsrcdir/build/mozconfig.no-compile
 
 # Build lightning locales
 ac_add_options --enable-calendar
 
 ac_add_options "MOZ_ALLOW_LEGACY_EXTENSIONS=1"
 # Disable checking that add-ons are signed by the trusted root
 MOZ_ADDON_SIGNING=0
 # Disable enforcing that add-ons are signed by the trusted root

--- a/mail/config/mozconfigs/win32/l10n-mozconfig
+++ b/mail/config/mozconfigs/win32/l10n-mozconfig
@@ -1,37 +1,30 @@
 . "$topsrcdir/build/mozconfig.comm-support"
 . "$topsrcdir/build/mozconfig.common"
 . "$topsrcdir/build/mozconfig.stylo"
 
 ac_add_options --enable-application=mail
 ac_add_options --enable-update-channel=${MOZ_UPDATE_CHANNEL}
 ac_add_options --with-l10n-base=../../l10n
-# The compile environment is needed for Windows, see bug 1345422 comment #58.
-# ac_add_options --disable-compile-environment
+. $topsrcdir/build/mozconfig.no-compile
 
 # Build lightning locales
 ac_add_options --enable-calendar
 
 # For NSS symbols
 export MOZ_DEBUG_SYMBOLS=1
 
 # Needed to enable breakpad in application.ini
 export MOZILLA_OFFICIAL=1
 
 ac_add_options "MOZ_ALLOW_LEGACY_EXTENSIONS=1"
 # Disable checking that add-ons are signed by the trusted root
 MOZ_ADDON_SIGNING=0
 # Disable enforcing that add-ons are signed by the trusted root
 MOZ_REQUIRE_ADDON_SIGNING=0
 
-. $topsrcdir/build/win32/mozconfig.vs-latest
-
-# Set up mapi includes (must be done after visual studio setup)
-export INCLUDE=$INCLUDE:/c/Office\ 2010\ Developer\ Resources/Outlook\ 2010\ MAPI\ Headers
-mk_export_correct_style INCLUDE
-
 # Run client.py
 mk_add_options CLIENT_PY_ARGS="$([ -f $topsrcdir/build/client.py-l10n-args ] && cat $topsrcdir/build/client.py-l10n-args)"
 mk_add_options ALWAYS_RUN_CLIENT_PY=1
 
 # Use the TOOLTOOL provided xz for mar generation.
 mk_add_options "export XZ=$TOOLTOOL_DIR/xz/xz.exe"

--- a/mail/config/mozconfigs/win64/l10n-mozconfig
+++ b/mail/config/mozconfigs/win64/l10n-mozconfig
@@ -1,35 +1,28 @@
 . "$topsrcdir/build/mozconfig.common"
 . "$topsrcdir/build/mozconfig.stylo"
 
 ac_add_options --target=x86_64-pc-mingw32
 ac_add_options --host=x86_64-pc-mingw32
 
 ac_add_options --enable-application=mail
 ac_add_options --enable-update-channel=${MOZ_UPDATE_CHANNEL}
-# The compile environment is needed for Windows, see bug 1345422 comment #58.
-# ac_add_options --disable-compile-environment
+. $topsrcdir/build/mozconfig.no-compile
 
 # Build lightning locales
 ac_add_options --enable-calendar
 
 # Needed to enable breakpad in application.ini
 export MOZILLA_OFFICIAL=1
 
 ac_add_options "MOZ_ALLOW_LEGACY_EXTENSIONS=1"
 # Disable checking that add-ons are signed by the trusted root
 MOZ_ADDON_SIGNING=0
 # Disable enforcing that add-ons are signed by the trusted root
 MOZ_REQUIRE_ADDON_SIGNING=0
 
-. $topsrcdir/build/win64/mozconfig.vs-latest
-
-# Set up mapi includes (must be done after visual studio setup)
-export INCLUDE=$INCLUDE:/c/Office\ 2010\ Developer\ Resources/Outlook\ 2010\ MAPI\ Headers
-mk_export_correct_style INCLUDE
-
 # Run client.py
 mk_add_options CLIENT_PY_ARGS="$([ -f $topsrcdir/build/client.py-args ] && cat $topsrcdir/build/client.py-args)"
 mk_add_options ALWAYS_RUN_CLIENT_PY=1
 
 # Use the TOOLTOOL provided xz for mar generation.
 mk_add_options "export XZ=$TOOLTOOL_DIR/xz/xz.exe"