global-functions: $WaitForFile: delay until "complete"...

Well, turns out that waiting for existence of a file is not sufficient.
Chances are that a file is available just partly, so wait until the size
no longer changes... Let's hope that works as expected. 🤞

global-functions.rsc

@@ -1577,6 +1577,16 @@
     :delay $Delay;
     :set I ($I + 1);
   }
+
+  :local File [ /file/find where name=$FileName ];
+  :local SizeA 0;
+  :local SizeB 1;
+  :while ($SizeA < $SizeB) do={
+    :set SizeA $SizeB;
+    :delay $Delay;
+    :set SizeB [ /file/get $File size ];
+  }
+
   :return true;
 }