diff --git a/toolkit/themes/gnomestripe/global/global.css b/toolkit/themes/gnomestripe/global/global.css
index 5e62089b2371..6a7c8e2e6101 100644
--- a/toolkit/themes/gnomestripe/global/global.css
+++ b/toolkit/themes/gnomestripe/global/global.css
@@ -161,7 +161,7 @@ sidebarheader:-moz-lwtheme {
 }
 
 :root:-moz-lwtheme-darktext {
-  text-shadow: 1px 1px 1.5px white;
+  text-shadow: 0 -0.5px 1.5px white;
 }
 
 :root:-moz-lwtheme-brighttext {
diff --git a/toolkit/themes/pinstripe/global/global.css b/toolkit/themes/pinstripe/global/global.css
index 53dacf273741..0be212c96bda 100644
--- a/toolkit/themes/pinstripe/global/global.css
+++ b/toolkit/themes/pinstripe/global/global.css
@@ -130,7 +130,7 @@ statusbarpanel {
 }
 
 :root:-moz-lwtheme-darktext {
-  text-shadow: 1px 1px 1.5px white;
+  text-shadow: 0 -0.5px 1.5px white;
 }
 
 :root:-moz-lwtheme-brighttext {
diff --git a/toolkit/themes/winstripe/global/global.css b/toolkit/themes/winstripe/global/global.css
index a75b99d54bef..9a8ae59c2451 100644
--- a/toolkit/themes/winstripe/global/global.css
+++ b/toolkit/themes/winstripe/global/global.css
@@ -162,7 +162,7 @@ toolbar[mode="text"] .toolbarbutton-text {
 }
 
 :root:-moz-lwtheme-darktext {
-  text-shadow: 1px 1px 1.5px white;
+  text-shadow: 0 -0.5px 1.5px white;
 }
 
 :root:-moz-lwtheme-brighttext {