Some alt key combinations not working on Mac

[Alex]

I'm using FileZilla version 3.33.0, on macOS High Sierra on an iMac, 21", Mid 2011. To use the "at" (@) key on my Spanish ISO keyboard I must pres Alt + 2 (both keys together). This works in all applications and screens o the system, but it's not working in the top most fields of Filezilla , where you enter Host, Username, Password and Port for Quickconnect. It seems to be using some other keyboard layout, just for that part. Specifically for the "@" character it shows nothing. If I use the keyboard on other places of Filezilla client (comments, etc.) the keys seems to be ok. This didn't happen with the previous version.