Control Chars on Entrytext

You should use >= instead of ≥. Don’t use a keyboard shortcut to insert the "greater than or equal to" operator — use the correct JavaScript syntax.

If that’s not the issue, try inserting the code below. It works in the attached .story file when the user clicks the Submit button.

var player = GetPlayer();

if(player.GetVar('entradadetexto').length >= 5) {
	alert('it is too long');
	player.SetVar('isDisabled', false);
} else {
	player.SetVar('isDisabled', true);
}

If it still doesn’t work, upload your slide so someone can take a look at the triggers setup.