Angular computed signals are not getting updated

Environment

OS: macOS 14.1.2
CPU: (10) arm64 Apple M1 Pro
Shell: /bin/zsh
node: 18.17.1
npm: 9.6.7
nativescript: 8.6.1

# android
java: 11.0.21
ndk: Not Found
apis: Not Found
build_tools: Not Found
system_images: Not Found

# ios
xcode: 15.1/15C65
cocoapods: 1.14.3
python: 3.11.6
python3: 3.11.6
ruby: 2.7.8
platforms: 
  - DriverKit 23.2
  - iOS 17.2
  - macOS 14.2
  - tvOS 17.2
  - watchOS 10.2

Dependencies

"dependencies": {
  "@angular/animations": "17.0.8",
  "@angular/common": "17.0.8",
  "@angular/compiler": "17.0.8",
  "@angular/core": "17.0.8",
  "@angular/forms": "17.0.8",
  "@angular/platform-browser": "17.0.8",
  "@angular/platform-browser-dynamic": "17.0.8",
  "@angular/router": "17.0.8",
  "@apollo/client": "3.8.8",
  "@mnd/external-web-view": "file:../app-plugins/dist/packages/external-web-view/mnd-external-web-view-1.0.1.tgz",
  "@nativescript/angular": "17.0.0",
  "@nativescript/core": "8.6.2",
  "@nativescript/iqkeyboardmanager": "2.1.1",
  "@nativescript/localize": "5.2.0",
  "@nativescript/mlkit-barcode-scanning": "file:../app-plugins-customized/mlkit/dist/packages/mlkit-barcode-scanning/nativescript-mlkit-barcode-scanning-2.0.0.tgz",
  "@nativescript/mlkit-core": "file:../app-plugins-customized/mlkit/dist/packages/mlkit-core/nativescript-mlkit-core-2.0.0.tgz",
  "@nativescript/secure-storage": "3.0.3",
  "@nativescript/theme": "3.0.2",
  "@nativescript/ui-charts": "0.2.4",
  "apollo-angular": "6.0.0",
  "apollo3-cache-persist": "0.14.1",
  "d3-ease": "3.0.1",
  "graphql": "16.8.1",
  "graphql-tag": "2.12.6",
  "intl": "1.2.5",
  "moment": "2.29.4",
  "nativescript-health-data": "file:../app-plugins-customized/nativescript-health-data/publish/package/nativescript-health-data-2.0.0.tgz",
  "nativescript-oauth2-ext": "file:../app-plugins-customized/nativescript-oauth2-ext/publish/package/nativescript-oauth2-ext-3.0.3.tgz",
  "nativescript-sqlite": "2.8.6",
  "nativescript-sqlite-commercial": "file:../app-plugins-customized/commercial-sqlite/nativescript-sqlite-commercial-1.8.0.tgz",
  "nativescript-sqlite-encrypted": "file:../app-plugins-customized/commercial-sqlite/nativescript-sqlite-encrypted-1.6.0.tgz",
  "nativescript-ui-calendar": "15.2.3",
  "nativescript-ui-gauge": "15.2.3",
  "qs": "npm:querystring@0.2.1",
  "rxjs": "7.8.1",
  "util": "0.12.5",
  "uuidjs": "5.0.1",
  "zone.js": "0.14.2"
},
"devDependencies": {
  "@angular-devkit/build-angular": "17.0.7",
  "@angular/compiler-cli": "17.0.8",
  "@graphql-codegen/cli": "5.0.0",
  "@graphql-codegen/fragment-matcher": "5.0.0",
  "@graphql-codegen/introspection": "4.0.0",
  "@graphql-codegen/typescript": "4.0.1",
  "@graphql-codegen/typescript-apollo-angular": "4.0.0",
  "@graphql-codegen/typescript-operations": "4.0.1",
  "@nativescript/android": "8.6.2",
  "@nativescript/ios": "8.6.3",
  "@nativescript/types": "8.6.1",
  "@nativescript/webpack": "5.0.18",
  "@ngtools/webpack": "17.0.7",
  "@types/d3-ease": "3.0.2",
  "@types/intl": "1.2.2",
  "@types/lodash": "^4.14.202",
  "@types/node": "20.10.5",
  "keycloak-request-token": "0.1.0",
  "rimraf": "5.0.5",
  "sass": "1.69.5",
  "ts-node": "10.9.2",
  "typescript": "5.2.2"
}

Describe the bug
I am currently upgrading my app to use Angulars new signal api. WritableSignal is working as expected. However computed signals seem to be not working correctly. My computed signals are initialised correctly but are not update if the referenced WritableSignal is updated with .set() or .update(()=>{}) functions. If I convert the WritabelSignal with toObservable() (my current workaorund) things are working as expected.

I am also observing that WritableSignal changes to not always lead to rerendering of the component. When changing the WritableSignal Value in the observable subscription as shown below, I have to call ChangeDetectorRef.detectChanges() to update the ui.

To Reproduce
Here is an example computed signal:
public _onSubMenuPage = computed(() => this.navSrv._currentRoute().startsWith('/sub-menu('));

This references:
public _currentRoute = signal('');

which I tried to update with .set() and .update() methods

Expected behavior
I expected the computed signal to be updated when its value changes to a different value than the current one.

Sample project

Additional context
When I convert the WritableSignal to an observable and subscribe to it, I get notfied through changes. This can be considered as a workaround as long as the computed methods is not working.

this._currentRoute$ = toObservable(this.navSrv._currentRoute);

Update: The issue might be related to the fact that I am using the signals in components that reside in different PageRouterOutlets. I can use an effect(()=>void) to update component state but than have to call ChangeDetectorRef.detectChanges() in order for the changes to get rendered.

Start by reproducing the computed signal example using _onSubMenuPage and _currentRoute, then compare direct signal updates with the toObservable workaround. Investigate signal updates and rendering across different PageRouterOutlets, including the need for ChangeDetectorRef.detectChanges(). Done means computed values update and components rerender without manual change detection.