pressKeys emulation is broken

[jason0x43]

In browsers using mostly or all W3C semantics, pressKeys uses simulated keyboard events. In these browsers, sending some characters such as keys.TAB doesn't work as expected.

Consider the following test:

import { suite, test } from 'intern/core/lib/interfaces/tdd';
import keys from 'intern/webdriver/keys';

suite('functional', () => {
	test('find link', test => {
		return test.remote
			.setFindTimeout(5000)
			.get('/tests/functional/page.html')
			.findById('username')
			.click()
			.pressKeys('testing' + keys.TAB)
			.sleep(20000);
	});
});

In Firefox 72 with geckodriver 0.26, using a simple test page, it results in the following:

Sending keys.TAB should cause the browser to behave as if a Tab key was pressed, not send a Unicode character.

Similar behavior was observed with Chrome 79 and Safari 13.

See also: theintern/leadfoot#110.

[kgibb]

I'd like to see this one implemented. I can workaround the issue in some test cases using Element.type but not all of them have inputs.