MIME Type could not be changed in 4.0.12

[IrPr]

Dear George,

When we upgraded to 4.0.12, custom mime type is not possible anymore

All the MIME Types are default, and when i modify that it will not affect, while in the previous versions it was working properly

Please take a look in it

PS: We expect you to care more to avoid such problems
Its really bad that an implemented feature to be missed in the next releases

Thanks