Capybara finds a button, but clicking on it does nothing

UPDATE: I removed most of the javascript dependencies and it worked. I don’t know which library or code is the evil part, I did not need anything.

simple form, two input fields and a button

fill_in 'cellNumber', :with => '13245678'
fill_in 'password', :with => 'mypass'
click_button('OK')

He finds a button, but nothing happens.

Important !, if I click on myself, everything works as expected.

   <button type="submit" id="loginid">OK</button>
</form>

Using ruby-debug, I found that find_button ("OK"). click returns "". If not found, it will cause an error. If I click manually in the firefox window, stopping the capybara test with sleep or debugging, I see (a window with focus) a blue frame appears around the button, because it was selected in some way.

In any case, I am close to testing a mental remedy right now ... Any suggestions?