Cannot display images in CodeIgniter

Folder structure is the following: I have project-root folder, which is the baseUrl.

It seems you are confusing baseUrl and folders in filesystem.
The project-root folder is not baseUrl.

baseUrl is a URL, not a folder or directory.

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I know the difference between baseUrl and filesystem. What I meant was - I manually set baseUrl to project-root

Just out of curiosity: can you add css files to your view files using base_url() ?

No. It does not work either. This is just crazy) External links work just fine though. The problem is in internal routing. I just do not know what exactly the problem is.

base_url() is your problem... is project-root a folder in which app and public are located?

Yes, that's right

Show your app\Config base_url setting.

What did you Try? What did you Get? What did you Expect?

Joined CodeIgniter Community 2009.  ( Skype: insitfx )

public string $baseURL = 'http://localhost:8080/project-root';

add a trailing slash:
public string $baseURL = 'http://localhost:8080/project-root/';

Did not help either(