[key bindings] Can't trigger commands with a character that requires two presses

[MarkZ3]

Using Theia master as of today, Electron example.
If I try to open a terminal with the keybinding Ctrl+`
It doesn't work. I use the French (Canada) keyboard layout (Linux) which requires to press the ` key twice because the first time is used to write a character with that accent (è, ù, à). When using an english/US physical keyboard, this key is the quote/double-quote key, so it's possible to reproduce this issue with an English physical keyboard configured with the French (Canada) layout.

This works correctly in VS Code.

[paul-marechal]

Part of the issue here: When we react to a keydown event, we check the following event properties, in that order:

- event.keyCode // locale-dependent
- event.keyIdentifier // locale-dependent and mostly deprecated
- event.which // locale-dependent and mostly deprecated
- event.code // locale-independent

Here is the result for a keydown event on the same physical key for two different keyboards:

(US International) code=Backquote, which=0, keyCode=0, key=Dead, locale=undefined, location=0
(French(Canadian)) code=Backquote, which=163, keyCode=163, key=#, locale=undefined, location=0

Note the common point: code=Backquote.

I think it shows which=0 keyCode=0 key=Dead when the key has to be pressed twice to get a result (in an input/textarea/etc).

In the case of the French(Canadian) keyboard, the keycode 163 seems to not even be mapped to anything back on a US keyboard.

How should we handle keybindings ? Should it be locale independent ? What would be the best conversion strategy ?

[svenefftinge]

It is because of this microsoft/monaco-editor#1233