Shader have to be recompiled upon PIE restart

Recently i’ve added a new effects pack to my project, then moved that folder, fixed up redirectors, saved and reopened the project. Besides that some of the materials were broken. Then i fixed these materials, but besides all materials working again, on PIE restart, and with deleting the saved and intermediate folder, some material shaders have to be recompiled upon restart.

There are no log errors, only these messages

Log
LogMaterial: Missing cached shader map for material M_ky_flare01_primitive, compiling.
LogMaterial: Missing cached shader map for material FMatExpressionPreview MaterialExpressionDepthFade_0, compiling.

Video

Why is this happening, what can i do to make sure these shaders stay?