RenderTexture Blackout on Mobile and WebGL: Solving the Issue of RawImage Display in Unity
There are a few potential solutions to the issue of a RenderTexture showing as black on a RawImage when building for Android/iOS and WebGL, but not in Editor mode:
Check the "Read/Write Enabled" option in the texture import settings for the RenderTexture. This must be enabled for mobile and WebGL platforms in order for the texture to be readable.
Make sure that the RenderTexture is being correctly applied to the RawImage's texture property. This can be done by double-checking the code or the inspector settings to ensure the correct texture is being used.
Make sure that the camera that is rendering the scene to the RenderTexture has a valid target texture assigned to it.
Make sure that you are using the correct format of the Render Texture, such as "Render Texture Format" in the camera component settings.
Check the camera's "Clear Flags" setting. It should be set to "Solid Color" or "Depth Only" to avoid issues with the RenderTexture.
If the problem is still persistent, you may try building the app with different architecture settings and see if that helps.
Check if the problem is only with specific device or OS, if so then you should look for that specific device/OS's compatibility with Unity.
If all above steps fails, consider creating a new Unity project and moving your assets to the new project.
It's also recommend to test the app on different devices and platforms, and to check the Unity console for any error messages that may provide more information about the issue.
