While we are on the subject, there is something strange occurring with the icon contained in the Pixel Thermometer app available on the GrapheneOS app store.
I use Smart Launcher as the default launcher. Among its features, it supports themed icons, including the ones generated algorithmically by the companion app Icon Pack Studio. Now, when there is no icon theme pack applied, the Pixel Thermometer icon is properly rendered, as per the screen snippet below:
No icon pack applied
However, when the Icon Pack Studio generated icons are applied (independently from the algorithm selected), the Pixel Thermometer icon is not drawn at all, as below:
With icon pack applied
You will pardon me for the eventual absurdity I am going to write, but it seems like the icon stored in the Pixel Thermometer app is not vectorial, or not standard. In the screen shot below there is another icon which does not behave correctly, the lite version of Trip Advisor provided by the Hermit app. Indeed, I opened a case also with the relative maintainer.
Yes, it's a nuisance, and to be honest it's not clear if the original app available on the stock firmware has the same issue, or not.