Your comments

I also used Photoshop to add the XMP test2.zip


But it still not show up in filerun.

I have just double checked with exiftool

exiftool.exe -xmp -b test.png > a.xmp

It does contain the following XMP

<?xpacket begin="" id="W5M0MpCehiHzreSzNTczkc9d"?>
<x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="XMP Core 5.6.0">
   <rdf:rdf xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
      <rdf:description rdf:about="" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:lr="http://ns.adobe.com/lightroom/1.0/" xmlns:photoshop="http://ns.adobe.com/photoshop/1.0/">
         <dc:description>Caption
</dc:description>
         <dc:rights>Copyrgiht</dc:rights>
         <dc:subject>
            <rdf:bag>
               <rdf:li>Filerun</rdf:li>
            </rdf:bag>
         </dc:subject>
         <lr:hierarchicalsubject>
            <rdf:bag>
               <rdf:li>Filerun</rdf:li>
            </rdf:bag>
         </lr:hierarchicalsubject>
         <photoshop:datecreated>2000-01-01T00:00:00</photoshop:datecreated>
      </rdf:description>
   </rdf:rdf>
</x:xmpmeta>

Here is a test file. 

I am using Docker with Software version 2018.11.11.

I have indexed the folder manually.

 Here is what I see in XnView MP.

I also used https://www.get-metadata.com to confirm XMP exists.