From 4c95ae546f5783b7dedf6885f6defcca07827d2f Mon Sep 17 00:00:00 2001
From: Jeremy Ruston <jeremy@jermolene.com>
Date: Fri, 7 Mar 2025 16:23:16 +0000
Subject: [PATCH] Fix colour-interpolate with missing colours

---
 core/modules/filters/colour-ops.js | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/core/modules/filters/colour-ops.js b/core/modules/filters/colour-ops.js
index 4e0e514f0..2828130c4 100644
--- a/core/modules/filters/colour-ops.js
+++ b/core/modules/filters/colour-ops.js
@@ -99,8 +99,11 @@ exports["colour-interpolate"] = function(source,operator,options) {
 		return [];
 	}
 	var colourA = $tw.utils.parseCSSColorObject(operator.operands[0]),
-		colourB = $tw.utils.parseCSSColorObject(operator.operands[1]),
-		rangefn = colourA.range(colourB,{space: space, hue: hueAdjuster});
+		colourB = $tw.utils.parseCSSColorObject(operator.operands[1]);
+	if(!colourA || !colourB) {
+		return [];
+	}
+	var rangefn = colourA.range(colourB,{space: space, hue: hueAdjuster});
 	// Cycle through the weights
 	var results = [];
 	source(function(tiddler,title) {