Starting with version 2.6.0, the MRTK shaders are being versioned via the MRTK.Shaders.sentinel file. When upgrading to a new version of MRTK, the following message may appear.
Selecting Yes instructs MRTK to overwrite the contents of Assets > MRTK > Shaders with the latest version. Selecting No will preserve the current files. Ignore will create a file (
IgnoreUpdateCheck.sentinel) in Assets > MRTK > Shaders, which will suppress future shader update checks.
When overwriting the shader files, any custom modifications will be lost. Be sure to backup any modified shader files before upgrading.
If the project has been configured to use the Universal Render Pipeline (URP) - formerly Lightweight Render Pipeline (LWRP), please re-run Mixed Reality > Toolkit > Utilities > Upgrade MRTK Standard Shader for Lightweight Render Pipeline.
At is also possible to check for shader updates at any time using Mixed Reality > Toolkit > Utilities > Check for Shader Updates on the Unity Editor's menu bar.
Check for Shader Updates disregards the
IgnoreUpdateCheck.sentinel file and allows on-demand shader updating.
Checking for shader updates is not required when importing the MRTK .unitypackage files.