Chrome for Android version 79 was released this week, and it brings a small change to how PWA icons are rendered when installed to user phones. (This is also how the new Firefox will render your icons when released!)
You may need to change you icon in order for it to look great in all different Android launchers out there, so here is a handy tool to do it:
If you want to learn more about it check out the tool creator blog post
Thank you for making this post! Some users on forums I help manage said the logo changed for their homescreen shortcuts recently, and this appears to be why 
Maskable was super useful!
It took me a few minutes of comparing image URLs to be sure which image in Discourse’s settings I needed to change-- as far as I can tell, it’s the “manifest icon”. Which now that I type it out makes sense, but I was scanning the settings for something mentioning Android. Hope this saves someone else a few minutes
