Apply ui modification

Hello everyone, i'm currently trying to modify traccar web app design css, add html and modify button. But my issue is, that any of my changes are applied. How can i fix this issue ? Thanks a lot.

You mean not applied? Are you clearing browser cache?

It's not a cache problem, for instance i modified the background-color in the app.css file. I use the script minify.sh to generate the app.min.js and i reload my apache server but nothing is chainging.

What is showing in the browser's inspector?

It's telling me this

filter_content.js:154 Uncaught (in promise) TypeError: Cannot read property 'appendChild' of null
    at FilterContent.initialize_ (filter_content.js:154)
    at filter_content.js:21

That's in the Console. What is in the Elements tab?

In the console.

Yes, in the console you saw that. But that is useless, irrelevant information.
You want to know why your styles are not being applied to specific elements, so you need to look in the elements tab.
If you look in the wrong place, you will not find what you seek.

I asked you a question. You didn't answer the question. Without that answer, not only am I unable to help, but I also suspect no-one can help.