Fix wrong context in reference widget lookups (senaite#1917)

* Use absolute context url for reference widget lookups

* Changelog updated

Author: ramonski

CHANGES.rst

@@ -4,6 +4,7 @@ Changelog
 2.2.0 (unreleased)
 ------------------
 
+- #1917 Fix wrong context in reference widget lookups
 - #1916 Provide the request record to object info adapters in the sample add form
 - #1913 Ported PR #1865 for dexterity contents
 - #1915 Support list queries in dx reference widget

src/senaite/core/browser/widgets/referencewidget.py

@@ -100,8 +100,14 @@ def get_combogrid_options(self, context, fieldName):
         colModel = self.colModel
         if "UID" not in [x["columnName"] for x in colModel]:
             colModel.append({"columnName": "UID", "hidden": True})
+
+        # ensure we have an absolute url for the current context
+        url = api.get_url(context)
+        search_path = self.url.split(url)[-1]
+        search_url = "/".join([url, search_path])
+
         options = {
-            "url": self.url,
+            "url": search_url,
             "colModel": colModel,
             "showOn": self.showOn,
             "width": self.popup_width,