setup (props) {
    onMounted(() => {
      <% if (ctx.mode.capacitor && metaConf.versions.capacitorPluginSplashscreen && capacitor.hideSplashscreen !== false) { %>
      SplashScreen.hide()
      <% } %>

      <% if (ctx.mode.ssr && ssr.manualPostHydrationTrigger !== true) { %>
      const { proxy: { $q } } = getCurrentInstance()
      $q.onSSRHydrated !== void 0 && $q.onSSRHydrated()
      <% } %>
    })

    return () => h(AppComponent, props)
  }
THIS FILE IS GENERATED AUTOMATICALLY.
DO NOT EDIT.

You are probably looking on adding startup/initialization code.
Use "quasar new boot <name>" and add it there.
One boot file per concern. Then reference the file(s) in quasar.config file > boot:
boot: ['file', ...] // do not add ".js" extension to it.

Boot files are your "main.js"