Here are some recommendations from a user on ticket 209843:

Print profiles should be independent of the materials they were created from.

Currently, importing print profiles will automatically put them under certain materials, even when other materials are selected & active.

(video on the email ticket going over adding a profile in Cura)

This is a big inconvenience for users that want to use a library of custom materials. Profiles should be independent of the materials and should automatically inherit the properties of the materials that they are inserted under.

Solution: Remove anything that intrinsically links a profile to a specific material by default. The only “link” should be dependent on the material that the profile is saved under in the [Preferences -> Configure Cura] menu. Inserting a profile when Material B is selected should not automatically put it under Material A.

Duplicating a custom material will instantly crash cura with no error message.
If I attempt to duplicate a custom material on Cura LulzBot Edition – 3.6.18, the program will instantly crash. Duplicating a pre-existing (default) material works fine but duplicating a custom material will crash the program. This will occur even with administrator access, so it is likely not a “write access” issue.