Electron setting transparent form is invalid

electron-vue for the project
create a transparent form
Code:

iconWindow = new BrowserWindow({
    // height: 100,
    // width: 100,
    frame: false,
    resizable: false,
    // x: -1000,
    // y: 50,
    transparent: true,
  })
  iconWindow.loadURL(miniWinURL)
  iconWindow.webContents.closeDevTools();

actual effect:

you can see that the
form has no shadow, which means that the transparent setting has taken effect, and I haven"t set the background color for
body and html.
but why isn"t it transparent?

Mar.07,2021

Debug window needs to be closed


set CSS


BrowserWindow frame transparent

win = new BrowserWindow({
    frame: false,
    transparent: true,
});

as a matter of fact, it has already been successful here. It is still white because of the devTool

.

close devTool, and refresh F5

Menu