I. Add/Remove actions.
1. Switch to HC Light (or HC Dark) theme
2. On Host level open Item inherited from Template
3. Open Preprocessing tab
4.1 Add action is disabled, but it doesn't look like that.
4.2 The same in Graph widget Settings Problems tab (Show problems - unchecked).
1. On Host level open Graph inherited from Template
2. Find Items section where Items added
3. Color picker looks like enabled while it is disabled.
Like in Trigger displaying options: