From c3266c2c52f65ad3c87a8ea88ab09393d90838ee Mon Sep 17 00:00:00 2001
From: Liviu-Mihail Concioiu <liviu.concioiu@gmail.com>
Date: Wed, 30 Apr 2025 19:23:30 +0200
Subject: [PATCH] Prevent ol.css being added multiple times

Signed-off-by: Liviu-Mihail Concioiu <liviu.concioiu@gmail.com>
---
 libraries/classes/Gis/GisVisualization.php | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/libraries/classes/Gis/GisVisualization.php b/libraries/classes/Gis/GisVisualization.php
index 8bdcae4e2b..92bd7b5fd6 100644
--- a/libraries/classes/Gis/GisVisualization.php
+++ b/libraries/classes/Gis/GisVisualization.php
@@ -434,7 +434,13 @@ class GisVisualization
         $output = 'function drawOpenLayers() {'
             . 'if (typeof ol !== "undefined") {'
             . 'var olCss = "js/vendor/openlayers/theme/ol.css";'
-            . '$(\'head\').append(\'<link rel="stylesheet" type="text/css" href=\'+olCss+\'>\');'
+            . 'if (!document.querySelector(\'link[rel="stylesheet"][href="\' + olCss + \'"]\')) {'
+            . 'var link = document.createElement(\'link\');'
+            . 'link.rel = \'stylesheet\';'
+            . 'link.type = \'text/css\';'
+            . 'link.href = olCss;'
+            . 'document.head.appendChild(link);'
+            . '}'
             . 'var vectorLayer = new ol.source.Vector({});'
             . 'var map = new ol.Map({'
             . 'target: \'openlayersmap\','