Merge pull request #1792 from umap-project/fix-title-html

fix: do not add title to button if content is a DOM node

umap/static/umap/js/umap.core.js

@@ -98,7 +98,9 @@ L.DomUtil.createFieldset = (container, legend, options) => {
 L.DomUtil.createButton = (className, container, content, callback, context) => {
   const el = L.DomUtil.add('button', className, container, content)
   el.type = 'button'
+  if (!content.nodeType) {
     el.title = content
+  }
   if (callback) {
     L.DomEvent.on(el, 'click', L.DomEvent.stop).on(el, 'click', callback, context)
   }