Internationalization combobox does not appear

Added two cultures (italian and english), italian as default, translated one italian resx, Run server, combobox on the top right does not appear.

Just tried the same and worked normally on my end:

Any ignored files in your app?

Hi Enchev,
no ignored files. I created from scratch the solution, and created a master detail set of forms. The only thing of strange I did is to rename them placing Add and Edit at the end of the name.

Hi Im having the same problem , internationalization enabled but no combobox.
I have also enabled the Security feature, i dont know if that would be an issue.

If it can help , now i can see the DropDown but everytime i try to run the app this error appears from that said dropdown.

Edit: Dropdown disappeared by just opening the project again.