Forcing fallback?

Is there any way to force unity to use fallback shaders instead of the selected shaders, even if our current hardware supports the shaders?

We just got a bugreport on one of our materials being broken on Linux. When investigating, I realized that the shader wasn't supported, and the fallback shader used the alpha differently, resulting in something that should've been a semi-transparent plane not being transparent.
We never caught this, because we never had any hardware/software setups where the shader failed in testing.

This made me wonder how many of our fallbacks that are actually working correctly. There's not really any good way to test them without getting hold of hardware/driver setups that triggers the fallback, which is not really viable. I'm not going to install Kubuntu+homebrew shader flavor 4 to see if things are broken there. So what I'm looking for is some way to force the fallback to happen, to test them.

The Graphics Emulation options doesn't seem to make a difference here. It's either exactly as in not emulated, or every single shader failing.