diff --git a/src/Magnum/Shaders/Line.in.vert b/src/Magnum/Shaders/Line.in.vert
index 2f0073f03..c91bd264c 100644
--- a/src/Magnum/Shaders/Line.in.vert
+++ b/src/Magnum/Shaders/Line.in.vert
@@ -45,7 +45,7 @@ highp vec2 expandLineVertex(
     in mediump const float width,
     in mediump const float smoothness,
     in highp const float miterLimit,
-    in lowp const vec2 viewportSize,
+    in highp const vec2 viewportSize,
     out highp vec2 centerDistanceSigned,
     out highp float halfSegmentLength,
     out highp float hasCap)
diff --git a/src/Magnum/Shaders/Line.vert b/src/Magnum/Shaders/Line.vert
index 2ae38bf2f..12c233333 100644
--- a/src/Magnum/Shaders/Line.vert
+++ b/src/Magnum/Shaders/Line.vert
@@ -302,7 +302,7 @@ highp vec2 expandLineVertex(
     in mediump const float width,
     in mediump const float smoothness,
     in highp const float miterLimit,
-    in lowp const vec2 viewportSize,
+    in highp const vec2 viewportSize,
     out highp vec2 centerDistanceSigned,
     out highp float halfSegmentLength,
     out highp float hasCap);