How can I run 'about:config' (or something like that) to find Clearly's variable called "extensions.readable-by-evernote.keys_speech".
In Polish standard keyboard layout right ALT + S is used to enter a special Polish letter 'ś'. So when I for example compose an email in Gmail and try to write this letter Clearly Text To Speech page is shown instead and makes the extension unusable.
about:config
Re: about:config
Not sure if it's the solution you're looking for but you can always make a script with Autohotkey that will override Clearly's keyboard shortcut