Vimium's detection of text entry forms

[tjhowse]

Very rarely I click on an input box or other text entry field and start typing, only to have Vimium catch the keystrokes rather than the text going into the field. Is there some general advice I could supply to a web developer to avoid this behaviour? I have to assume it's because of some slightly off-piste deb development. An example of such behaviour can be found in the comment box on articles on jank dot cool.

To be clear: Vimium behaves as expected in 99.95% of cases. It's just the occasional weird website that trips it up.