We use different languages for keyboard input including the US keyboard with Vietnamese characters from the settings/keyboard/layout panel in Ubuntu-Studio 19.10 (xfce).
Using the Vietnamese keyboard variant seems to be our main issue, as: where are the Vietnamese characters? How does one produce the required accented characters? How to use the "Compose" key, or rather, what are the required character sequences to get the Vietnamese accented characters.
A visual display showing this would be nice, but xkeycaps does not seem to know about Vietnamese characters.
The physical keyboard is PC 105 keys.
Where could we find the relevant information?
Thank you,
ac