From 24749a3595d604c27449bcf2fce85c0907f41012 Mon Sep 17 00:00:00 2001
From: Volker E <volker.e@wikimedia.org>
Date: Thu, 26 Mar 2020 20:12:12 -0700
Subject: [PATCH] Use `calc` in `font-size` to harmonize IE 9-11

IE 9-11 cuts values 2 digits after the decimal point leading
to small miscalculations throughout the interface derived from `.mw-body-content`'s `em` value.
With `calc` it's forced to use same parent value for its
rendering calculations.

Bug: T102364
Change-Id: Id4ba39bc90174bab445ae0fb4d039c28a4f0b300
---
 resources/skins.vector.styles/common.less | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/resources/skins.vector.styles/common.less b/resources/skins.vector.styles/common.less
index 8d5b0e3..5abf0dd 100644
--- a/resources/skins.vector.styles/common.less
+++ b/resources/skins.vector.styles/common.less
@@ -97,6 +97,9 @@ body {
 .mw-body-content {
 	position: relative;
 	font-size: @font-size-base;
+	// Support IE 9-11, Trident cuts values 2 digits after decimal point.
+	// `calc` enables to set correct calculation in place again. See T102364.
+	font-size: calc( 1em ~'*' unit( @font-size-base ) );
 	line-height: @line-height-base;
 	z-index: 0;