Why do I get white screen when building flutter web

Question

I want to build a flutter web app, so I enter 'webdev build' command and after the operation finishes, I open the 'index.html' file located in build directory and it's just a white screen. I tried it on a fresh project and the problem persists. There's no problem during developing.

Here's my flutter doctor output:

Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel stable, v1.5.4-hotfix.2, on Microsoft Windows [Version 10.0.17134.766], locale en-US)

[√] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[√] Android Studio (version 3.3)
[√] VS Code (version 1.35.1)
[!] Connected device
    ! No devices available

! Doctor found issues in 1 category.

Answer 1

For me seemed to have been a problem with antivirus and running flutter run -d chrome --release solved my problem.

Answer 2

You have to upload your files to the server and put them inside the root folder.

If you want to put them in other folder, you have to edit the "index.html" file to tell hem the folder.

For example: If you upload your files to "test" folder, you have to edit this line of "index.html":

<base href="/">

To

<base href="/test/">