Lovalce modules

Hello everybody, I try to play with this example - https://developers.home-assistant.io/docs/frontend/custom-ui/lovelace-custom-card/
First time it has been installed and works. But when I try to change something in js file it doesn’t works - my new code doesn’t update. I had tryed to reload HA and reboot system - nothing happens. HA show me old/first example.

Have you cleared the cache of your browser (ctrl-F5 or “empty cache & hard reload” from the F12 menu in chrome)?

I have tryied a lot of of variouse combination - clean cache, reload HA and reboot. Finally I have came to mind that I need to create js template that will have a constant content with links to jq and css files. In this case I will have possibility to make changes without reloading (it takes time), without cleaning cache (it deletes login, pass that also add more routines).
How do you think is it good way? But I’m not sure where I have to put my jq, css files that will be visible/accessible for main component.