From 26c733e237ad7da90a7a2f83fc0d51d2f8d69015 Mon Sep 17 00:00:00 2001
From: John McLear <john@mclear.co.uk>
Date: Thu, 7 Jan 2021 20:19:36 +0000
Subject: [PATCH]  better handling of line heights

---
 src/static/js/scroll.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/static/js/scroll.js b/src/static/js/scroll.js
index 31a9dccd2..34d9868a6 100644
--- a/src/static/js/scroll.js
+++ b/src/static/js/scroll.js
@@ -356,13 +356,14 @@ Scroll.prototype.movePage = function (direction) {
   const buffer = 25;
   // we need to remember that lineoffset needs to be removed too..
   let offset = linePosition.bottom - viewport.top;
+  let lineHeight = linePosition.top - linePosition.bottom;
   let pixelsToScroll = viewport.top - viewport.bottom + offset;
   if (direction === 'up') {
     // buffer pixels unscrolled our safety net here.  You can't use the current or previous
     // line height because it might be a very long line..
-    pixelsToScroll = -Math.abs(pixelsToScroll + buffer/2);
+    pixelsToScroll = -Math.abs(pixelsToScroll - lineHeight);
   } else {
-    pixelsToScroll = Math.abs(pixelsToScroll + buffer/2);
+    pixelsToScroll = Math.abs(pixelsToScroll - lineHeight);
   }
 
   this.outerWin.scrollBy(0, pixelsToScroll);