How to reproduce:
1. Open the attached project ("Showcase.zip")
2. Find the "LWRP-HighQuality" file in the Project Window
3. Toggle the "Opaque Texture" setting on and off and observe that there are no changes in the Game Window
4. Build the game with the "Opaque Texture" setting and observe the scene

Expected result: when the "Opaque Texture" setting is on the scenes are visually identical in both Editor and Standalone Build
Actual result: when the "Opaque Texture" setting is on in the build, the "hand" objects are visible and the camera's black opaque background is copied over around them. In the Editor the "Opaque Texture" setting does nothing whether It's on or off and both the "hand" and the standard scene objects are visible.

Reproduced in: 2019.3.0a5, 2019.2.0b5 (With LWRP 6.5.3; 6.5.2; 5.16.1)
Couldn't test with: LWRP 6.7.1 (The project breaks on this version and multiple errors are thrown)

Note: the "depth" texture seems to be copied over correctly but the changes are not visible in the Game Window