Problems typing accented words

Hello, I am using google translator.
I am having a problem trying to type accented words in my application.
In Ubuntu 16.04, when trying to type accented words they don’t appear.
In Ubuntu 18.04, the accents appear, but not the right way.

The following image shows the results found and the expected result.

My application (vlibras-desktop) uses Unity. I think this is a problem with the snap configuration, as the application was also made for Windows and is working perfectly there. In windows I am using the keyboard format PT.BR ABNT2. In ubuntu I’m using Portuguese (Brazil). I can use accents normally in the system. This problem only happens within the application.

In snapcraft.yaml I am using a desktop-launch (desktop-gtk3).
Plugs: home, desktop, desktop-legacy, x11, network, opengl, unity7

Did you find a fix?