I usually use URP and have had no problems with the UI Outline shader, even for large rings of outlined effects.
In a test project using built-in render pipeline, I noticed that there was a 1px wide artifact at the outer edge, most of the way around the outline mesh. I tried every parameter I could think of, to remove the artifact. It seems like the kind of artifact from a UV-coord edge being set to a "Repeat" wrap value, instead of a "Clamp" value.
In the end, I made the mesh-generating code just generate UV coordinates from V=0f to V=0.98f instead of 0f to 1f, but that's an unsatisfying hack to work around the issue. I didn't have ASE to dig into the shader to see if there was an easy fix to clamp the UV at the outer edge.
I usually use URP and have had no problems with the UI Outline shader, even for large rings of outlined effects.
In a test project using built-in render pipeline, I noticed that there was a 1px wide artifact at the outer edge, most of the way around the outline mesh. I tried every parameter I could think of, to remove the artifact. It seems like the kind of artifact from a UV-coord edge being set to a "Repeat" wrap value, instead of a "Clamp" value.
In the end, I made the mesh-generating code just generate UV coordinates from V=0f to V=0.98f instead of 0f to 1f, but that's an unsatisfying hack to work around the issue. I didn't have ASE to dig into the shader to see if there was an easy fix to clamp the UV at the outer edge.