If this mod v1.4 still work fine for v1.5. Here is how to added v1.5 tag to remove annoying yellow text in the game.

1. First go to the game mod folder.
   It's either SteamLibrary\Steamapps\common\RimWorld\Mods if you download mod manual.
   If using Steam workshop go to SteamLibrary\steamapps\workshop\content\294100\2420141361
   294100 is Game ID. 2420141361 is Mod ID can be found in the url. This work for all mod ID.
   
2. Go to about folder and open About.xml with app like Notepad or Notepad++ or Wordpad.
   
3. You will see something like this
   <ModMetaData>
   <name>Quality Colors</name>
   <author>legodude17</author>
   <url></url>
   <description>Colors the items in the trade window based on quality.</description>
   <packageId>legodude17.qualcolor</packageId>
   <supportedVersions>
   <li>1.2</li>
   <li>1.3</li>
   <li>1.4</li>
   </supportedVersions>
   ...................................................................................and more
   
4. added another line of code below 1.4 with the exact space just change 1.4 to 1.5
   
5. You all set, now you can play the game and see it no longer show yellow warning.

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This only change the game tag to regconize it's v1.5. It doesn't change the mod core, only how it get regconize by the game to not output yellow warning.
So only do this you certainly know old mod work fine in v1.5 and wanted to remove warning sign.
That's for all, happy coding