It's not actually just a warning -

[JijaProGamer]

If I Run

openupm add com.unity.nuget.newtonsoft-json@3.0.2

(Also tried 3.2.1, since 3.0.3 your library wants doesn't actually exist)

and then

openupm add com.lachee.discordrpc

I get this warning:

error CS1566: Error reading resource 'DiscordRPC.xml' -- 'Could not find a part of the path 'C:\Users\bloxx\FitZen VR\Packages\com.lachee.discordrpc\Runtime\DiscordRPC.xml'.'

Which won't allow me to actually run the build

[TornadoOfSoup]

I think this may be due to a missing .meta file for DiscordRPC.xml. I noticed that DiscordRPC.xml exists in the folder when viewed in File Explorer, but doesn't have a .meta file. Every other file with a .meta file in that directory appears properly in the editor, and when I tried renaming or copying DiscordRPC.xml, Unity gave this warning:

Asset Packages/com.lachee.discordrpc/Runtime/DiscordRPC.xml has no meta file, but it's in an immutable folder. The asset will be ignored.

Maybe since it's in an immutable folder when imported as a package, it's unable to generate the .meta file? In this case, it might work fine in development, since I imagine it would be in a normal mutable folder rather than in the package folder Unity doesn't want to touch.

[xflipperkast]

same issue here

[Snow0406]

same issue here

[aDu]

Same.

[gage-langdon]

I found a workaround. I moved the package to /scripts/ and modified the csc.rsp file from packages to /res:Assets/Scripts/com.lachee.discordrpc/Runtime/DiscordRPC.xml and the same in Editor/NativeDLLHandler.cs

[aDu]

Searching around the code for references, I think it might be due to the following:

• UNITY_2019_OR_NEWER possibly not working on newer Unity versions [source: https://discussions.unity.com/t/unity_2019_or_newer-not-recognised-in-unity-2020/815014/3]
• In Editor/NativeDllHandler.cs, the call to FixLinkerSettings() create these files in the condition that !UNITY_2019_OR_NEWER

I have not tested this to confirm. Someone can test and add a pull request if they want to try fix this, but otherwise, I was able to install the package (via the "+" icon in Unity and entering the Git URL) and treat it as a warning, so I think it's not critical to fix.

Edit:

The warnings are:

• Asset Packages/com.lachee.discordrpc/Runtime/DiscordRPC.xml has no meta file, but it's in an immutable folder. The asset will be ignored.
• Asset Packages/com.lachee.discordrpc/Runtime/csc.rsp has no meta file, but it's in an immutable folder. The asset will be ignored.

The errors are:

• error CS1566: Error reading resource 'DiscordRPC.xml' -- 'Could not find a part of the path 'D:\unity-projects\PianoViz\Packages\com.lachee.discordrpc\Runtime\DiscordRPC.xml'.'

[aDu]

After using it for a few days I now get that error and it wouldn't let me run my game.

I had to manually add the file to the location to make it work

[LaymGlitched]

my workaround was to drag the Packages/Discord Rich Presence folder to the ProjectFolder/Packages folder

[aDu]

Another workaround is to just add the UNITY_2019_OR_NEWER directive manually. I made a PR to fix it: #16