Index: skins/common/diff.js
===================================================================
--- skins/common/diff.js	(revision 0)
+++ skins/common/diff.js	(revision 0)
@@ -0,0 +1,20 @@
+/*
+Workaround for overflow bug in Mozilla 1.1 and earlier, where scrolling
+<div>s in <td> cells collapse their height to a single line.
+
+Known to be fixed in 1.2.1 (Gecko 20021130), but the CSS hacks I've tried
+with overflow-x disable the scrolling all the way until Mozilla 1.8 / FF 1.5
+and break Opera as well.
+
+So... we check for reaaaally old Gecko and hack in an alternate rule to let
+the wide cells spill instead of scrolling them. Not ideal as it won't work
+if JS is disabled, of course.
+*/
+
+if (navigator && navigator.product == "Gecko" && navigator.productSub < "20021130") {
+	var sheets = document.styleSheets;
+	var lastSheet = sheets[sheets.length-1];
+	lastSheet.insertRule(
+		"table.diff td div { overflow: visible; }",
+		lastSheet.cssRules.length);
+}
\ No newline at end of file

Property changes on: skins/common/diff.js
___________________________________________________________________
Name: svn:eol-style
   + native

Index: skins/common/diff.css
===================================================================
--- skins/common/diff.css	(revision 22407)
+++ skins/common/diff.css	(working copy)
@@ -62,4 +62,13 @@
 	/* As fallback, scrollbars will be added for very wide cells
 	   instead of text overflowing or widening */
 	overflow: auto;
+	
+	/* The above rule breaks on very old versions of Mozilla due
+	   to a bug which collapses the table cells to a single line.
+	   
+	   In Mozilla 1.1 and below with JavaScript enabled, the rule
+	   will be overridden with this by diff.js; wide cell contents
+	   then spill horizontally without widening the rest of the
+	   table: */
+	/* overflow: visible; */
 }
Index: includes/DifferenceEngine.php
===================================================================
--- includes/DifferenceEngine.php	(revision 22407)
+++ includes/DifferenceEngine.php	(working copy)
@@ -296,11 +296,22 @@
 			$wgOut->addWikitext( wfMsg( 'missingarticle', "<nowiki>(fixme, bug)</nowiki>" ) );
 			return false;
 		} else {
-			$wgOut->addStyle( 'common/diff.css' );
+			$this->showDiffStyle();
 			$wgOut->addHTML( $diff );
 			return true;
 		}
 	}
+	
+	/**
+	 * Add style sheets and supporting JS for diff display.
+	 */
+	function showDiffStyle() {
+		global $wgStylePath;
+		$wgOut->addStyle( 'common/diff.css' );
+		
+		// JS is needed to detect old versions of Mozilla to work around an annoyance bug.
+		$wgOut->addScript( "<script type=\"text/javascript\" src=\"$wgStylePath/common/diff.js\"></script>" );
+	}
 
 	/**
 	 * Get diff table, including header